Vaccines

14 pages, 293 KB

Open AccessEditor’s ChoiceArticle

Risk of Repeated Adverse Effects following Booster Dose of mRNA COVID-19 Vaccine: Results from the MOSAICO Study

by Pietro Ferrara, Domenico Ponticelli, Lorenzo Losa, Claudia Romeo, Roberto Magliuolo, Andrea Vitale, Anna Zampella, Lucia Alleanza, Mario Borrelli, Beniamino Schiavone and Lorenzo Giovanni Mantovani

Vaccines 2023, 11(2), 247; https://doi.org/10.3390/vaccines11020247 - 22 Jan 2023

Cited by 12 | Viewed by 4987

Abstract

The successful deployment of safe and effective vaccines against coronavirus disease 2019 (COVID-19) has been crucial in reducing the global disease burden. Owing to the need for vaccination series over time, continuous observational studies are needed to estimate the COVID-19 vaccine response in [...] Read more.

The successful deployment of safe and effective vaccines against coronavirus disease 2019 (COVID-19) has been crucial in reducing the global disease burden. Owing to the need for vaccination series over time, continuous observational studies are needed to estimate the COVID-19 vaccine response in real-world conditions. In particular, the detection, assessment, and understanding of adverse effects following immunization (AEFI) with a COVID-19 vaccine are crucial to better address vaccination strategies. Therefore, this study aimed to investigate the risk of repeated AEFI post-administration of a booster dose of mRNA COVID-19 vaccine in a sample of healthcare workers (HCWs) in an Italian teaching hospital. The data on any local and systemic AEFI were studied in multivariate Poisson regression analyses to model the association between the incidence of each postvaccination symptom and its prior reporting after the administration of the previous doses. Overall, compared with the primary vaccination series, the majority of post-third dose AEFI were less reported. The results from multivariable models showed that the likelihood of reporting an AEFI after the third dose was higher in those who experienced the same postvaccination symptom after the second dose (all AEFI except for itch at injection site) and, although not significant for all AEFI, after the first dose. Any associations with age, gender, smoking habits, previous SARS-CoV-2 infection and other characteristics, as well as the health impact of AEFI were also assessed. Taken together, the results from this research support reframe AEFI symptoms as signals of a robust postvaccination reaction as well as of common vaccine response, and they add important data to inform booster vaccination strategies in HCWs and, extensively, in the adult population. Full article

(This article belongs to the Special Issue Research on Immune Response and Vaccines)

22 pages, 1178 KB

Open AccessEditor’s ChoiceReview

Myeloid-Derived Suppressor Cells in Cancer and COVID-19 as Associated with Oxidative Stress

by Celia María Curieses Andrés, José Manuel Pérez de la Lastra, Celia Andrés Juan, Francisco J. Plou and Eduardo Pérez-Lebeña

Vaccines 2023, 11(2), 218; https://doi.org/10.3390/vaccines11020218 - 19 Jan 2023

Cited by 7 | Viewed by 3587

Abstract

Myeloid-derived suppressor cells MDSCs are a heterogeneous population of cells that expand beyond their physiological regulation during pathologies such as cancer, inflammation, bacterial, and viral infections. Their key feature is their remarkable ability to suppress T cell and natural killer NK cell responses. [...] Read more.

Myeloid-derived suppressor cells MDSCs are a heterogeneous population of cells that expand beyond their physiological regulation during pathologies such as cancer, inflammation, bacterial, and viral infections. Their key feature is their remarkable ability to suppress T cell and natural killer NK cell responses. Certain risk factors for severe COVID-19 disease, such as obesity and diabetes, are associated with oxidative stress. The resulting inflammation and oxidative stress can negatively impact the host. Similarly, cancer cells exhibit a sustained increase in intrinsic ROS generation that maintains the oncogenic phenotype and drives tumor progression. By disrupting endoplasmic reticulum calcium channels, intracellular ROS accumulation can disrupt protein folding and ultimately lead to proteostasis failure. In cancer and COVID-19, MDSCs consist of the same two subtypes (PMN-MSDC and M-MDSC). While the main role of polymorphonuclear MDSCs is to dampen the response of T cells and NK killer cells, they also produce reactive oxygen species ROS and reactive nitrogen species RNS. We here review the origin of MDSCs, their expansion mechanisms, and their suppressive functions in the context of cancer and COVID-19 associated with the presence of superoxide anion ^•O₂⁻ and reactive oxygen species ROS. Full article

(This article belongs to the Section Veterinary Vaccines)

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14 pages, 263 KB

Open AccessEditor’s ChoiceArticle

Rural Americans’ COVID-19 Vaccine Perceptions and Willingness to Vaccinate against COVID-19 with Their Community Pharmacists: An Exploratory Study

by Alexis M. Koskan, Iris E. LoCoco, Casey L. Daniel and Benjamin S. Teeter

Vaccines 2023, 11(1), 171; https://doi.org/10.3390/vaccines11010171 - 13 Jan 2023

Cited by 15 | Viewed by 4641

Abstract

In early 2022 in the U.S., rural adults were the least likely to vaccinate against COVID-19 due to vaccine hesitancy and reduced healthcare access. This study explored the factors influencing rural adults’ COVID-19 vaccine perceptions and their acceptance of pharmacist-administered vaccination. We utilized [...] Read more.

In early 2022 in the U.S., rural adults were the least likely to vaccinate against COVID-19 due to vaccine hesitancy and reduced healthcare access. This study explored the factors influencing rural adults’ COVID-19 vaccine perceptions and their acceptance of pharmacist-administered vaccination. We utilized phone-based semi-structured interviews with 30 adults living in rural regions of one southwestern state and analyzed the data using a team-based thematic analysis approach. Vaccine-willing participants described knowing other people affected by the virus and their desired protection from the virus. They reported trusting scientific institutions and the government to provide safe vaccines. Vaccine-hesitant populations, however, feared that the COVID-19 vaccine development process had been rushed, compromising the safety of these newer vaccines. Although they differed in the news sources they preferred for receiving COVID-19 vaccine information, both vaccine-willing and vaccine-hesitant participants described trusting local authorities, such as healthcare providers and county government officials, to provide accurate COVID-19 vaccine information. Regarding the acceptability of pharmacist-administered COVID-19 vaccinations, all but one participant described their acceptance of this healthcare delivery approach. Future outreach should leverage rural adults’ trust in local sources, including community pharmacists, deemed more convenient access points to healthcare, when addressing vaccine hesitancy. Full article

(This article belongs to the Special Issue Recent Advances in Factors Associated with Vaccine Hesitancy and Acceptance)

11 pages, 280 KB

Open AccessEditor’s ChoiceArticle

Seasonal Influenza Vaccine Intention among Nurses Who Have Been Fully Vaccinated against COVID-19: Evidence from Greece

by Petros Galanis, Aglaia Katsiroumpa, Irene Vraka, Olga Siskou, Olympia Konstantakopoulou, Theodoros Katsoulas and Daphne Kaitelidou

Vaccines 2023, 11(1), 159; https://doi.org/10.3390/vaccines11010159 - 11 Jan 2023

Cited by 11 | Viewed by 3853

Abstract

Seasonal influenza continues to be a significant public health issue causing hundreds of thousands of deaths annually. Nurses are a priority risk group for influenza vaccination and a high vaccine uptake rate among them is crucial to protect public health. Thus, the aim [...] Read more.

Seasonal influenza continues to be a significant public health issue causing hundreds of thousands of deaths annually. Nurses are a priority risk group for influenza vaccination and a high vaccine uptake rate among them is crucial to protect public health. Thus, the aim of our study was to estimate the levels of influenza vaccine acceptance, as well as its determinants, among nurses for the 2022/2023 season. We conducted a cross-sectional study with a convenience sample in Greece. We collected data via an online survey in September 2022. Most of the nurses in the study possessed a MSc/PhD diploma (56.2%) and had previously been infected by SARS-CoV-2 (70.3%). Among nurses, 57.3% were willing to accept the influenza vaccine, 19% were hesitant, and 23.7% were unwilling. Older age, higher levels of perceived support from significant others, and higher COVID-19-related physical exhaustion were positively related to influenza vaccination intention. In contrast, more side effects because of COVID-19 vaccination and higher levels of exhaustion due to measures taken against COVID-19 were negatively associated with vaccination intention. Since the influenza vaccination acceptance rate among nurses was moderate, policymakers should develop and implement measures tailored specifically to nurses in the context of the COVID-19 pandemic to decrease vaccine hesitancy. Full article

(This article belongs to the Special Issue Vaccines Hesitancy and Public Health)

12 pages, 1707 KB

Open AccessEditor’s ChoiceArticle

SARS-CoV-2 mRNA Dual Immunization Induces Innate Transcriptional Signatures, Establishes T-Cell Memory and Coordinates the Recall Response

by Ioanna Papadatou, Maria Geropeppa, Kleio-Maria Verrou, Marianna Tzanoudaki, Theano Lagousi, Emmanouil Liatsis and Vana Spoulou

Vaccines 2023, 11(1), 103; https://doi.org/10.3390/vaccines11010103 - 1 Jan 2023

Cited by 3 | Viewed by 3454

Abstract

Background: mRNA vaccines have played a crucial role in controlling the SARS-CoV-2 global pandemic. However, the immunological mechanisms involved in the induction, magnitude and longevity of mRNA-vaccine-induced protective immunity are still unclear. Methods: In our study, we used whole-RNA sequencing along with detailed [...] Read more.

Background: mRNA vaccines have played a crucial role in controlling the SARS-CoV-2 global pandemic. However, the immunological mechanisms involved in the induction, magnitude and longevity of mRNA-vaccine-induced protective immunity are still unclear. Methods: In our study, we used whole-RNA sequencing along with detailed immunophenotyping of antigen-specific T cells and humoral RBD-specific response to dual immunization with the Pfizer–BioNTech mRNA vaccine (BNT162b2) and correlated them with response to an additional dose, administered 10 months later, in order to comprehensively profile the immune response of healthy volunteers to BNT162b2. Results: Primary dual immunization induced upregulation of the Type I interferon pathway and generated spike protein (S)-specific IFN-γ+ and TNF-α+ CD4 T cells, S-specific memory CD4 T cells, and RBD-specific antibodies against SARS-CoV-2. S-specific CD4 T cells induced by the primary series correlated with the RBD-specific antibody titers to a third dose. Conclusions: This study demonstrates the induction of both innate and adaptive immunity in response to the BNT162b2 mRNA vaccine in a coordinated manner and identifies the central role of primarily induced CD4+ T cells as a predictive biomarker of the magnitude of anamnestic immune response. Full article

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10 pages, 887 KB

Open AccessEditor’s ChoiceArticle

Slower Waning of Anti-SARS-CoV-2 IgG Levels Six Months after the Booster Dose Compared to Primary Vaccination

by Sanja Zember, Kristian Bodulić, Nataša Cetinić Balent, Radojka Mikulić, Alemka Markotić and Oktavija Đaković Rode

Vaccines 2022, 10(11), 1813; https://doi.org/10.3390/vaccines10111813 - 28 Oct 2022

Cited by 7 | Viewed by 2293

Abstract

Anti-SARS-CoV-2 IgG titer decreases rapidly after primovaccination, leading to a mandatory booster vaccination. We analysed anti-SARS-CoV-2 Spike RBD IgG levels (positive ≥ 50 AU/mL) in 405 healthcare workers (3010 sera) who received a booster dose (BD) 9 months after two-dose BNT162b2 primovaccination. Median [...] Read more.

Anti-SARS-CoV-2 IgG titer decreases rapidly after primovaccination, leading to a mandatory booster vaccination. We analysed anti-SARS-CoV-2 Spike RBD IgG levels (positive ≥ 50 AU/mL) in 405 healthcare workers (3010 sera) who received a booster dose (BD) 9 months after two-dose BNT162b2 primovaccination. Median antibody titer at the time of BD (582.6 AU/mL) was 1.7-fold and 16.4-fold lower than the peak titer after the first (961.5 AU/mL) and the second vaccine dose (SVD) (10,232.6 AU/mL), respectively. One month after vaccination, IgG titer increased 40.6-fold after BD compared with a 10.8-fold increase after primovaccination. Three months after vaccination, post-booster antibodies decreased significantly slower (2.2-fold) than after primovaccination (3.3-fold). At six months, antibodies decreased slower after BD (4.5-fold; median 5556.0 AU/mL) than after primovaccination (9.6-fold; median 1038.5 AU/mL). Antibody titers before and one month after BD correlated weakly (r = 0.30) compared with a strong correlation (r = 0.65) between the corresponding post-primovaccination titers. Pre-vaccination COVID-19 had no effect on IgG levels after BD compared with a positive effect after primovaccination. Despite high post-booster IgG levels, 22.5% of participants contracted mild COVID-19. The trend of IgG decline indicates the need for further revaccination, but the vaccine type should be defined according to viral mutations. Full article

(This article belongs to the Special Issue Effectiveness, Safety and Immunogenicity of SARS-CoV-2 Vaccines)

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21 pages, 1575 KB

Open AccessEditor’s ChoiceReview

Antibody-Based Immunotherapies as a Tool for Tackling Multidrug-Resistant Bacterial Infections

by António M. M. Seixas, Sílvia A. Sousa and Jorge H. Leitão

Vaccines 2022, 10(11), 1789; https://doi.org/10.3390/vaccines10111789 - 25 Oct 2022

Cited by 29 | Viewed by 5446

Abstract

The discovery of antimicrobials is an outstanding achievement of mankind that led to the development of modern medicine. However, increasing antimicrobial resistance observed worldwide is rendering commercially available antimicrobials ineffective. This problem results from the bacterial ability to adapt to selective pressure, leading [...] Read more.

The discovery of antimicrobials is an outstanding achievement of mankind that led to the development of modern medicine. However, increasing antimicrobial resistance observed worldwide is rendering commercially available antimicrobials ineffective. This problem results from the bacterial ability to adapt to selective pressure, leading to the development or acquisition of multiple types of resistance mechanisms that can severely affect the efficacy of antimicrobials. The misuse, over-prescription, and poor treatment adherence by patients are factors strongly aggravating this issue, with an epidemic of infections untreatable by first-line therapies occurring over decades. Alternatives are required to tackle this problem, and immunotherapies are emerging as pathogen-specific and nonresistance-generating alternatives to antimicrobials. In this work, four types of antibody formats and their potential for the development of antibody-based immunotherapies against bacteria are discussed. These antibody isotypes include conventional mammalian polyclonal antibodies that are used for the neutralization of toxins; conventional mammalian monoclonal antibodies that currently have 100 IgG mAbs approved for therapeutic use; immunoglobulin Y found in birds and an excellent source of high-quality polyclonal antibodies able to be purified noninvasively from egg yolks; and single domain antibodies (also known as nanobodies), a recently discovered antibody format (found in camelids and nurse sharks) that allows for a low-cost synthesis in microbial systems, access to hidden or hard-to-reach epitopes, and exhibits a high modularity for the development of complex structures. Full article

(This article belongs to the Special Issue Microbial Antigen Identification and Vaccine Delivery Systems)

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17 pages, 298 KB

Open AccessEditor’s ChoiceReview

COVID-19 Vaccine-Associated Optic Neuropathy: A Systematic Review of 45 Patients

by Ayman G. Elnahry, Mutaz Y. Al-Nawaflh, Aisha A. Gamal Eldin, Omar Solyman, Ahmed B. Sallam, Paul H. Phillips and Abdelrahman M. Elhusseiny

Vaccines 2022, 10(10), 1758; https://doi.org/10.3390/vaccines10101758 - 20 Oct 2022

Cited by 17 | Viewed by 6843

Abstract

We provide a systematic review of published cases of optic neuropathy following COVID-19 vaccination. We used Ovid MEDLINE, PubMed, and Google Scholar. Search terms included: “COVID-19 vaccination”, “optic neuropathy”, “optic neuritis”, and “ischemic optic neuropathy”. The titles and abstracts were screened, then the [...] Read more.

We provide a systematic review of published cases of optic neuropathy following COVID-19 vaccination. We used Ovid MEDLINE, PubMed, and Google Scholar. Search terms included: “COVID-19 vaccination”, “optic neuropathy”, “optic neuritis”, and “ischemic optic neuropathy”. The titles and abstracts were screened, then the full texts were reviewed. Sixty eyes from forty-five patients (28 females) were included. Eighteen eyes from fourteen patients (31.1%) were diagnosed with anterior ischemic optic neuropathy (AION), while 34 eyes from 26 patients (57.8%) were diagnosed with optic neuritis (ON). Other conditions included autoimmune optic neuropathy and Leber hereditary optic neuropathy. Fifteen patients (33.3%) had bilateral involvement. The mean age of all patients was 47.4 ± 17.1 years. The mean age of AION patients was 62.9 ± 12.2 years and of ON patients was 39.7 ± 12.8 years (p < 0.001). The mean time from vaccination to ophthalmic symptoms was 9.6 ± 8.7 days. The mean presenting visual acuity (VA) was logMAR 0.990 ± 0.924. For 41 eyes with available follow-up, the mean presenting VA was logMAR 0.842 ± 0.885, which improved to logMAR 0.523 ± 0.860 at final follow-up (p < 0.001). COVID-19 vaccination may be associated with different forms of optic neuropathy. Patients diagnosed with ON were more likely to be younger and to experience visual improvement. More studies are needed to further characterize optic neuropathies associated with COVID-19 vaccination. Full article

(This article belongs to the Special Issue Ophthalmic Adverse Events following SARS-CoV-2 Vaccination)

11 pages, 1302 KB

Open AccessEditor’s ChoiceArticle

Relationship between Anti-Spike Antibodies and Risk of SARS-CoV-2 Infection in Infants Born to COVID-19 Vaccinated Mothers

by Madeleine D. Burns, Cordelia Muir, Caroline Atyeo, Jameson P. Davis, Stepan Demidkin, Babatunde Akinwunmi, Alessio Fasano, Kathryn J. Gray, Galit Alter, Lydia L. Shook, Andrea G. Edlow and Lael M. Yonker

Vaccines 2022, 10(10), 1696; https://doi.org/10.3390/vaccines10101696 - 11 Oct 2022

Cited by 17 | Viewed by 3855

Abstract

The goal of this study was to investigate the relationship between anti-SARS-CoV-2-Spike IgG titers passively transferred to the fetus from maternal vaccination during pregnancy and timing of infant SARS-CoV-2 infection. Pregnant, vaccinated individuals (n = 105) and their infants (n = 107) were [...] Read more.

The goal of this study was to investigate the relationship between anti-SARS-CoV-2-Spike IgG titers passively transferred to the fetus from maternal vaccination during pregnancy and timing of infant SARS-CoV-2 infection. Pregnant, vaccinated individuals (n = 105) and their infants (n = 107) were enrolled in a prospective cohort study from July 2021 to June 2022, linking infant anti-Spike IgG titer at birth to risk of SARS-CoV-2 infection in the first fifteen months of life. Cord blood sera were collected at delivery and infant sera were collected at two and six months of age. Anti-SARS-CoV-2-Spike IgG levels were quantified in cord and infant sera using an enzyme-linked immunosorbent assay. Infants were followed for SARS-CoV-2 infection through fifteen months of age. Anti-SARS-CoV-2-Spike IgG titers in infants declined significantly with increased age (p < 0.001). Infants with higher anti-Spike cord blood levels had significantly longer disease-free intervals prior to infection with SARS-CoV-2 (p = 0.027). While higher anti-Spike IgG titer at two months of age was associated with a longer interval to infection through nine months of age (p = 0.073), infant anti-Spike IgG titers by six months of age had no impact on disease-free interval. This cohort study suggests that passively transferred maternal IgG is protective against infant SARS-CoV-2 infection, with higher antibody levels at birth significantly associated with longer disease-free intervals. Infant antibodies and protection from SARS-CoV-2 infection wane significantly after six months, suggesting that vaccination is needed at this stage to optimize protection against COVID-19. Full article

(This article belongs to the Special Issue Research on Immune Response and Vaccines)

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12 pages, 903 KB

Open AccessEditor’s ChoiceReview

Timing of the First Dose of the Hepatitis B Vaccine in Preterm Infants

by Donna Lei, Taryn Miller, Jeremy Carr, Jim Buttery, Claudia A. Nold-Petry, Marcel F. Nold and Atul Malhotra

Vaccines 2022, 10(10), 1656; https://doi.org/10.3390/vaccines10101656 - 2 Oct 2022

Cited by 8 | Viewed by 3731

Abstract

Introduction: The World Health Organization (WHO) recommends all newborn infants receive the first dose of the hepatitis B vaccine within 24 h of birth irrespective of maternal hepatitis B carrier status. However, the physiological immaturity of the immune system in preterm infants may [...] Read more.

Introduction: The World Health Organization (WHO) recommends all newborn infants receive the first dose of the hepatitis B vaccine within 24 h of birth irrespective of maternal hepatitis B carrier status. However, the physiological immaturity of the immune system in preterm infants may influence the immune responses to the vaccine particularly in the first few days and weeks of life, and adverse events may occur following vaccination that are not observed in infants born at term. Objectives: To review existing published guidelines surrounding timing of the first dose of the hepatitis B vaccine in preterm infants born to hepatitis B surface antigen negative (HBsAg-negative) mothers. Methods: A search was performed for relevant papers and guidelines published between January 2002 and July 2022 on the Ovid MEDLINE and Embase databases and through targeted searches. Two authors independently reviewed the search results to identify relevant sources, which were then analysed and described through narrative synthesis. Results: Twenty-seven relevant papers and guidelines regarding 15 countries and regions were included. Of these, 13.3% of guidelines, which represented 16.8% of the overall population of 4.1 billion people covered by the identified guidelines, recommended a nationwide birth dose of the hepatitis B vaccine to all preterm infants. In 40.0% of guidelines (77.9% of the overall population), the birth dose was only recommended for infants with a birth weight of more than 2000–2200 g. Another 33.3% of countries and regions (covering 4.4% of the population) recommended no universal birth dose for all infants, including preterm infants, whilst 13.3% (1.0% of the population) had guidelines that varied between jurisdictions and hospitals within their country/region. Conclusions: Existing guidelines surrounding the timing of the first dose of the hepatitis B vaccine in preterm infants vary substantially between countries and regions. Further research comparing the immunogenicity and safety of different hepatitis B vaccine schedules is needed to provide concrete evidence to provide guidance regarding the timing of vaccination against hepatitis B in preterm infants. Full article

(This article belongs to the Special Issue Pediatric Infectious Disease and Vaccination)

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14 pages, 339 KB

Open AccessEditor’s ChoiceReview

A Vaccine for Canine Rocky Mountain Spotted Fever: An Unmet One Health Need

by David H. Walker, Lucas S. Blanton, Maureen Laroche, Rong Fang and Hema P. Narra

Vaccines 2022, 10(10), 1626; https://doi.org/10.3390/vaccines10101626 - 28 Sep 2022

Cited by 11 | Viewed by 3889

Abstract

Outbreaks of life-threatening Rocky Mountain spotted fever in humans and dogs associated with a canine-tick maintenance cycle constitute an important One Health opportunity. The reality of the problem has been observed strikingly in Mexico, Brazil, Colombia, and Native American tribal lands in Arizona. [...] Read more.

Outbreaks of life-threatening Rocky Mountain spotted fever in humans and dogs associated with a canine-tick maintenance cycle constitute an important One Health opportunity. The reality of the problem has been observed strikingly in Mexico, Brazil, Colombia, and Native American tribal lands in Arizona. The brown dog tick, Rhipicephalus sanguineus sensu lato, acquires the rickettsia from bacteremic dogs and can maintain the bacterium transtadially to the next tick stage. The subsequent adult tick can then transmit infection to a new host, as shown by guinea pig models. These brown dog ticks maintain spotted fever group rickettsiae transovarially through many generations, thus serving as both vector and reservoir. Vaccine containing whole-killed R. rickettsii does not stimulate sufficient immunity. Studies of Rickettsia subunit antigens have demonstrated that conformationally preserved outer-membrane autotransporter proteins A and B are the leading vaccine candidates. The possibility of a potentially safe and effective live attenuated vaccine has only begun to be explored as gene knockout methods are applied to these obligately intracellular pathogens. Full article

(This article belongs to the Special Issue Immunity and Vaccination against Bacterial Infections)

17 pages, 668 KB

Open AccessEditor’s ChoiceArticle

Determinants of Antibody Responses to SARS-CoV-2 Vaccines: Population-Based Longitudinal Study (COVIDENCE UK)

by David A. Jolliffe, Sian E. Faustini, Hayley Holt, Natalia Perdek, Sheena Maltby, Mohammad Talaei, Matthew Greenig, Giulia Vivaldi, Florence Tydeman, Jane Symons, Gwyneth A. Davies, Ronan A. Lyons, Christopher J. Griffiths, Frank Kee, Aziz Sheikh, Seif O. Shaheen, Alex G. Richter and Adrian R. Martineau

Vaccines 2022, 10(10), 1601; https://doi.org/10.3390/vaccines10101601 - 23 Sep 2022

Cited by 27 | Viewed by 4453

Abstract

Antibody responses to SARS-CoV-2 vaccines vary for reasons that remain poorly understood. A range of sociodemographic, behavioural, clinical, pharmacologic and nutritional factors could explain these differences. To investigate this hypothesis, we tested for presence of combined IgG, IgA and IgM (IgGAM) anti-Spike antibodies [...] Read more.

Antibody responses to SARS-CoV-2 vaccines vary for reasons that remain poorly understood. A range of sociodemographic, behavioural, clinical, pharmacologic and nutritional factors could explain these differences. To investigate this hypothesis, we tested for presence of combined IgG, IgA and IgM (IgGAM) anti-Spike antibodies before and after 2 doses of ChAdOx1 nCoV-19 (ChAdOx1, AstraZeneca) or BNT162b2 (Pfizer-BioNTech) in UK adults participating in a population-based longitudinal study who received their first dose of vaccine between December 2020 and July 2021. Information on sixty-six potential sociodemographic, behavioural, clinical, pharmacologic and nutritional determinants of serological response to vaccination was captured using serial online questionnaires. We used logistic regression to estimate multivariable-adjusted odds ratios (aORs) for associations between independent variables and risk of seronegativity following two vaccine doses. Additionally, percentage differences in antibody titres between groups were estimated in the sub-set of participants who were seropositive post-vaccination using linear regression. Anti-spike antibodies were undetectable in 378/9101 (4.2%) participants at a median of 8.6 weeks post second vaccine dose. Increased risk of post-vaccination seronegativity associated with administration of ChAdOx1 vs. BNT162b2 (adjusted odds ratio (aOR) 6.6, 95% CI 4.2–10.4), shorter interval between vaccine doses (aOR 1.6, 1.2–2.1, 6–10 vs. >10 weeks), poor vs. excellent general health (aOR 3.1, 1.4–7.0), immunodeficiency (aOR 6.5, 2.5–16.6) and immunosuppressant use (aOR 3.7, 2.4–5.7). Odds of seronegativity were lower for participants who were SARS-CoV-2 seropositive pre-vaccination (aOR 0.2, 0.0–0.6) and for those taking vitamin D supplements (aOR 0.7, 0.5–0.9). Serologic responses to vaccination did not associate with time of day of vaccine administration, lifestyle factors including tobacco smoking, alcohol intake and sleep, or use of anti-pyretics for management of reactive symptoms after vaccination. In a sub-set of 8727 individuals who were seropositive post-vaccination, lower antibody titres associated with administration of ChAdOx1 vs. BNT162b2 (43.4% lower, 41.8–44.8), longer duration between second vaccine dose and sampling (12.7% lower, 8.2–16.9, for 9–16 weeks vs. 2–4 weeks), shorter interval between vaccine doses (10.4% lower, 3.7–16.7, for <6 weeks vs. >10 weeks), receiving a second vaccine dose in October–December vs. April–June (47.7% lower, 11.4–69.1), older age (3.3% lower per 10-year increase in age, 2.1–4.6), and hypertension (4.1% lower, 1.1–6.9). Higher antibody titres associated with South Asian ethnicity (16.2% higher, 3.0–31.1, vs. White ethnicity) or Mixed/Multiple/Other ethnicity (11.8% higher, 2.9–21.6, vs. White ethnicity), higher body mass index (BMI; 2.9% higher, 0.2–5.7, for BMI 25–30 vs. <25 kg/m²) and pre-vaccination seropositivity for SARS-CoV-2 (105.1% higher, 94.1–116.6, for those seropositive and experienced COVID-19 symptoms vs. those who were seronegative pre-vaccination). In conclusion, we identify multiple determinants of antibody responses to SARS-CoV-2 vaccines, many of which are modifiable. Full article

(This article belongs to the Special Issue Antibody Response of Vaccines to SARS-CoV-2)

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10 pages, 1674 KB

Open AccessEditor’s ChoiceArticle

Antibody Titers and Protection against Omicron (BA.1 and BA.2) SARS-CoV-2 Infection

by Chloé Dimeglio, Marion Migueres, Naémie Bouzid, Sabine Chapuy-Regaud, Caroline Gernigon, Isabelle Da-Silva, Marion Porcheron, Guillaume Martin-Blondel, Fabrice Herin and Jacques Izopet

Vaccines 2022, 10(9), 1548; https://doi.org/10.3390/vaccines10091548 - 17 Sep 2022

Cited by 33 | Viewed by 3067

Abstract

The emergence of the SARS-CoV-2 variants of concern has greatly influenced the immune correlates of protection, and there are little data about the antibody threshold concentrations to protect against infection with SARS-CoV-2 Omicron BA.1 or BA.2. We analyzed the antibody responses of 259 [...] Read more.

The emergence of the SARS-CoV-2 variants of concern has greatly influenced the immune correlates of protection, and there are little data about the antibody threshold concentrations to protect against infection with SARS-CoV-2 Omicron BA.1 or BA.2. We analyzed the antibody responses of 259 vaccinated healthcare workers, some of whom had been previously infected by SARS-CoV-2. The median follow-up was 179 days (IQR: 171–182) after blood collection. We detected 88 SARS-CoV-2 Omicron infections during the follow-up period, 55 (62.5%) with SARS-CoV-2 BA.1, and 33 (37.5%) with SARS-CoV-2 BA.2. A neutralizing antibody titer below 8 provided no protection against a BA.1 infection, a titer of 16 or 32 gave 73.2% protection, and a titer of 64 or 128 provided 78.4% protection. Conversely, the BA.2 infection rate did not vary as a function of anti-BA.2 neutralizing antibody titers. Binding antibody concentrations below 6000 BAU/mL provided no protection against Omicron BA.1 infection, 6000–20,000 BAU/mL provided 55.6% protection, and 20,000 or more provided 87.7% protection. There was no difference in BA.2 infection depending on the binding antibody concentration. Further studies are needed to investigate the relationship between antibody concentrations and infection with the Omicron BA.4/5 variants that are becoming predominant worldwide. Full article

(This article belongs to the Special Issue Influence of Natural and/or Vaccine Immunity on the Dynamics of SARS-CoV-2)

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18 pages, 4289 KB

Open AccessEditor’s ChoiceArticle

Microneedle Delivery of an Adjuvanted Microparticulate Vaccine Induces High Antibody Levels in Mice Vaccinated against Coronavirus

by Sharon Vijayanand, Smital Patil, Devyani Joshi, Ipshita Menon, Keegan Braz Gomes, Akanksha Kale, Priyal Bagwe, Shadi Yacoub, Mohammad N. Uddin and Martin J. D’Souza

Vaccines 2022, 10(9), 1491; https://doi.org/10.3390/vaccines10091491 - 7 Sep 2022

Cited by 16 | Viewed by 4341

Abstract

This ‘proof-of-concept’ study aimed to test the microparticulate vaccine delivery system and a transdermal vaccine administration strategy using dissolving microneedles (MN). For this purpose, we formulated poly(lactic-co-glycolic) acid (PLGA) microparticles (MP) encapsulating the inactivated canine coronavirus (iCCoV), as a model antigen, along with [...] Read more.

This ‘proof-of-concept’ study aimed to test the microparticulate vaccine delivery system and a transdermal vaccine administration strategy using dissolving microneedles (MN). For this purpose, we formulated poly(lactic-co-glycolic) acid (PLGA) microparticles (MP) encapsulating the inactivated canine coronavirus (iCCoV), as a model antigen, along with adjuvant MP encapsulating Alhydrogel^® and AddaVax. We characterized the vaccine MP for size, surface charge, morphology, and encapsulation efficiency. Further, we evaluated the in vitro immunogenicity, cytotoxicity, and antigen-presentation of vaccine/adjuvant MP in murine dendritic cells (DCs). Additionally, we tested the in vivo immunogenicity of the MP vaccine in mice through MN administration. We evaluated the serum IgG, IgA, IgG1, and IgG2a responses using an enzyme-linked immunosorbent assay. The results indicate that the particulate form of the vaccine is more immunogenic than the antigen suspension in vitro. We found the vaccine/adjuvant MP to be non-cytotoxic to DCs. The expression of antigen-presenting molecules, MHC I/II, and their costimulatory molecules, CD80/40, increased with the addition of the adjuvants. Moreover, the results suggest that the MP vaccine is cross presented by the DCs. In vivo, the adjuvanted MP vaccine induced increased antibody levels in mice following vaccination and will further be assessed for its cell-mediated responses. Full article

(This article belongs to the Special Issue Novel Vaccine Stabilization and Delivery Technologies)

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8 pages, 265 KB

Open AccessEditor’s ChoiceArticle

Differences in Long-COVID Symptoms between Vaccinated and Non-Vaccinated (BNT162b2 Vaccine) Hospitalized COVID-19 Survivors Infected with the Delta Variant

by César Fernández-de-las-Peñas, Ricardo Ortega-Santiago, Stella Fuensalida-Novo, José D. Martín-Guerrero, Oscar J. Pellicer-Valero and Juan Torres-Macho

Vaccines 2022, 10(9), 1481; https://doi.org/10.3390/vaccines10091481 - 6 Sep 2022

Cited by 19 | Viewed by 4960

Abstract

This study compared differences in the presence of post-COVID symptoms among vaccinated and non-vaccinated COVID-19 survivors requiring hospitalization due to the Delta (B.1.617.2) variant. This cohort study included hospitalized subjects who had survived SARS-CoV-2 infection (Delta variant) from July to August 2021 in [...] Read more.

This study compared differences in the presence of post-COVID symptoms among vaccinated and non-vaccinated COVID-19 survivors requiring hospitalization due to the Delta (B.1.617.2) variant. This cohort study included hospitalized subjects who had survived SARS-CoV-2 infection (Delta variant) from July to August 2021 in an urban hospital in Madrid, Spain. Individuals were classified as vaccinated if they received full administration (i.e., two doses) of BNT162b2 (“Pfizer-BioNTech”) vaccines. Other vaccines were excluded. Those with just one dose of the BNT162b2 vaccine were considered as non-vaccinated. Patients were scheduled for a telephone interview at a follow-up around six months after infection for assessing the presence of post-COVID symptoms with particular attention to those symptoms starting after acute infection and hospitalization. Anxiety/depressive levels and sleep quality were likely assessed. Hospitalization and clinical data were collected from medical records. A total comprising 109 vaccinated and 92 non-vaccinated COVID-19 survivors was included. Vaccinated patients were older and presented a higher number of medical comorbidities, particular cardiorespiratory conditions, than non-vaccinated patients. No differences in COVID-19 onset symptoms at hospitalization and post-COVID symptoms six months after hospital discharge were found between vaccinated and non-vaccinated groups. No specific risk factor for any post-COVID symptom was identified in either group. This study observed that COVID-19 onset-associated symptoms and post-COVID symptoms six-months after hospitalization were similar between previously hospitalized COVID-19 survivors vaccinated and those non-vaccinated. Current data can be applied to the Delta variant and those vaccinated with BNT162b2 (Pfizer-BioNTech) vaccine. Full article

(This article belongs to the Special Issue Assessment of Post-COVID-19 Complications and Vaccination Efficacy)

15 pages, 3695 KB

Open AccessEditor’s ChoiceArticle

A Bivalent Trans-Amplifying RNA Vaccine Candidate Induces Potent Chikungunya and Ross River Virus Specific Immune Responses

by Christin Schmidt, Florian D. Hastert, Julia Gerbeth, Tim Beissert, Ugur Sahin, Mario Perkovic and Barbara S. Schnierle

Vaccines 2022, 10(9), 1374; https://doi.org/10.3390/vaccines10091374 - 23 Aug 2022

Cited by 17 | Viewed by 4416

Abstract

Alphaviruses such as the human pathogenic chikungunya virus (CHIKV) and Ross River virus (RRV) can cause explosive outbreaks raising public health concerns. However, no vaccine or specific antiviral treatment is yet available. We recently established a CHIKV vaccine candidate based on trans-amplifying RNA [...] Read more.

Alphaviruses such as the human pathogenic chikungunya virus (CHIKV) and Ross River virus (RRV) can cause explosive outbreaks raising public health concerns. However, no vaccine or specific antiviral treatment is yet available. We recently established a CHIKV vaccine candidate based on trans-amplifying RNA (taRNA). This novel system consists of a replicase-encoding mRNA and a trans-replicon (TR) RNA encoding the antigen. The TR-RNA is amplified by the replicase in situ. We were interested in determining whether multiple TR-RNAs can be amplified in parallel and if, thus, a multivalent vaccine candidate can be generated. In vitro, we observed an efficient amplification of two TR-RNAs, encoding for the CHIKV and the RRV envelope proteins, by the replicase, which resulted in a high antigen expression. Vaccination of BALB/c mice with the two TR-RNAs induced CHIKV- and RRV-specific humoral and cellular immune responses. However, antibody titers and neutralization capacity were higher after immunization with a single TR-RNA. In contrast, alphavirus-specific T cell responses were equally potent after the bivalent vaccination. These data show the proof-of-principle that the taRNA system can be used to generate multivalent vaccines; however, further optimizations will be needed for clinical application. Full article

(This article belongs to the Special Issue mRNA Vaccine Development against Tropical Diseases)

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10 pages, 256 KB

Open AccessEditor’s ChoiceArticle

Rapid Implementation of a Community–Academic Partnership Model to Promote COVID-19 Vaccine Equity within Racially and Ethnically Minoritized Communities

by Jacinda C. Abdul-Mutakabbir, Cristie Granillo, Bridgette Peteet, Alex Dubov, Susanne B. Montgomery, Jasmine Hutchinson, Samuel Casey, Kelvin Simmons, Alex Fajardo and Juan Carlos Belliard

Vaccines 2022, 10(8), 1364; https://doi.org/10.3390/vaccines10081364 - 20 Aug 2022

Cited by 17 | Viewed by 3203

Abstract

Coronavirus disease 2019 (COVID-19) has highlighted inequities in mortalities and associated illnesses among non-Hispanic Black and Hispanic/Latino individuals. Immunization against COVID-19 is critical to ending the pandemic, especially within racial and ethnically minoritized communities. However, vaccine hesitancy and institutional mistrust in these communities, [...] Read more.

Coronavirus disease 2019 (COVID-19) has highlighted inequities in mortalities and associated illnesses among non-Hispanic Black and Hispanic/Latino individuals. Immunization against COVID-19 is critical to ending the pandemic, especially within racial and ethnically minoritized communities. However, vaccine hesitancy and institutional mistrust in these communities, resulting from decades of mistreatment, structural racism, and barriers to vaccination access, have translated into low vaccination uptake. Trustworthy relationships with healthcare professionals and partnerships with faith and community leaders are critical to increasing vaccination rates within these minoritized communities. Loma Linda University researchers collaborated with local faith and community organizations in San Bernardino County, CA, to rapidly implement a three-tiered approach to increase the vaccination rates within non-Hispanic Black and Hispanic/Latino communities. This community–academic partnership model provided over 1700 doses of the COVID-19 vaccine within these vaccine-hesitant, targeted minoritized communities. As over 100,000 individuals are diagnosed with COVID-19 daily and updated vaccines targeting variants of the Omicron strain are expected to rollout in the coming months, the development of sustainable programs aimed at increasing vaccine uptake within vulnerable communities are of the utmost importance. Full article

(This article belongs to the Collection COVID-19 Vaccine Hesitancy: Correlates and Interventions)

11 pages, 818 KB

Open AccessEditor’s ChoiceArticle

Time-Varying Effect of Hybrid Immunity on the Risk of Breakthrough Infection after Booster Dose of mRNA COVID-19 Vaccine: The MOSAICO Study

by Pietro Ferrara, Domenico Ponticelli, Roberto Magliuolo, Mario Borrelli, Beniamino Schiavone and Lorenzo Giovanni Mantovani

Vaccines 2022, 10(8), 1353; https://doi.org/10.3390/vaccines10081353 - 19 Aug 2022

Cited by 10 | Viewed by 3805

Abstract

This longitudinal observational study investigated the risk of breakthrough SARS-CoV-2 infection up to 6 months after a booster dose of an mRNA COVID-19 vaccine in infection-naïve vs. previously infected healthcare workers (HCWs), and whether this difference varied over time. A Cox proportional hazard [...] Read more.

This longitudinal observational study investigated the risk of breakthrough SARS-CoV-2 infection up to 6 months after a booster dose of an mRNA COVID-19 vaccine in infection-naïve vs. previously infected healthcare workers (HCWs), and whether this difference varied over time. A Cox proportional hazard regression model with Aalen’s additive analysis was fitted to examine the association between the risk of infections and predictor variables. Overall, we observed an incidence rate of 2.5 cases per 1000 person-days (95% confidence interval [CI] 2.0–3.0), which dropped at 0.8 per 1000 person-days (95% CI 0.3–2.0) in recipients with prior SARS-CoV-2 infection. The fitted analysis indicated an adjusted hazard ratio of 0.32 (95% CI 0.13–0.80; p-value = 0.01) for those with hybrid immunity with a slope that became steeply negative roughly starting from day 90. No difference was seen according to participants’ smoking habits. Characteristics of infected HCWs were also described. Our study quantifies the time-varying effects of vaccine-induced and hybrid immunity after the booster dose (during the Omicron variant predominance in Italy) and observed that the protection waned more rapidly in infection-naïve recipients starting from the third month. The results add important evidence that can be used to inform COVID-19 vaccination strategies. Full article

(This article belongs to the Special Issue Assessment of Post-COVID-19 Complications and Vaccination Efficacy)

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9 pages, 251 KB

Open AccessEditor’s ChoiceArticle

Young Age, Female Sex, and No Comorbidities Are Risk Factors for Adverse Reactions after the Third Dose of BNT162b2 COVID-19 Vaccine against SARS-CoV-2: A Prospective Cohort Study in Japan

by Ryuta Urakawa, Emiko Tanaka Isomura, Kazuhide Matsunaga and Kazumi Kubota

Vaccines 2022, 10(8), 1357; https://doi.org/10.3390/vaccines10081357 - 19 Aug 2022

Cited by 8 | Viewed by 5416

Abstract

Background: This study compared the adverse events (AEs) of the second and third doses of BNT162b2, as well as investigated the impact of vaccine recipients’ background and vaccination interval on the AEs of the third dose. Methods: We conducted a questionnaire survey of [...] Read more.

Background: This study compared the adverse events (AEs) of the second and third doses of BNT162b2, as well as investigated the impact of vaccine recipients’ background and vaccination interval on the AEs of the third dose. Methods: We conducted a questionnaire survey of AEs among health care workers at Osaka University Dental Hospital. Chi-square tests were performed to compare AEs to the administration of second and third vaccine doses. Logistic regression analyses were conducted to identify factors influencing the presence of AEs using age, sex, comorbidities, and the vaccination interval. Spearman’s rank correlation coefficient was calculated to investigate the correlation between age, vaccination interval, and severity of each AE. Results: The third dose of BNT162b2 was associated with significantly more frequent or milder AEs than the second dose. Logistic regression analyses detected significant differences in six items of AEs by age, three by sex, two by comorbidities, and zero by vaccination interval. Consistently, the risk of AEs was greater among younger persons, females, and those without comorbidities. Significant negative correlations were detected between age and vaccination interval, and between age and the severity of most AEs. Conclusions: Young, female, and having no comorbidities are risk factors for AEs after the third dose of BNT162b2, while vaccination interval is not. Full article

(This article belongs to the Special Issue The Current Situation and Future Perspective of Vaccines against Infectious Diseases in Children and Women)

12 pages, 280 KB

Open AccessEditor’s ChoiceReview

Vaccination for Monkeypox Virus Infection in Humans: A Review of Key Considerations

by Kay Choong See

Vaccines 2022, 10(8), 1342; https://doi.org/10.3390/vaccines10081342 - 18 Aug 2022

Cited by 44 | Viewed by 5847

Abstract

Monkeypox virus infection in humans (MVIH) is currently an evolving public health concern given that >3000 MVIH cases have been reported in >50 countries globally, and the World Health Organization declared monkeypox a global health emergency on 23 July 2022. Adults (≥16 years [...] Read more.

Monkeypox virus infection in humans (MVIH) is currently an evolving public health concern given that >3000 MVIH cases have been reported in >50 countries globally, and the World Health Organization declared monkeypox a global health emergency on 23 July 2022. Adults (≥16 years old) usually have mild disease in contemporary studies, with a pooled case fatality rate of 0.03% (1/2941 cases). In comparison, poorer outcomes have been reported in children <16 years old (pooled case fatality rate 19% (4/21 cases)), immunocompromised patients, and pregnant women, with high rates of fetal demise in this group. Monkeypox-specific treatments include oral or intravenous tecovirimat, intravenous or topical cidofovir, oral brincidofovir, and vaccinia immunoglobulin, but the overall risk–benefit balance of monkeypox-specific treatment is unclear. Two effective vaccines exist for the prevention of MVIH: modified vaccinia Ankara and ACAM2000. Most probably, vaccination will be a key strategy for mitigating MVIH given the current rapid global spread of monkeypox, the existence of efficacious vaccines, and the uncertain risk–benefit profile of current antivirals. Priority groups for vaccination should include healthcare workers at high risk for occupational exposure, immunocompromised patients, and children. Vaccination strategies include pre-exposure vaccination, post-exposure prophylaxis, and ring vaccination of close contacts. Full article

(This article belongs to the Special Issue Vaccination for Monkeypox Infection in Humans)

10 pages, 1092 KB

Open AccessEditor’s ChoiceArticle

Correlation between Adverse Events and Antibody Titers among Healthcare Workers Vaccinated with BNT162b2 mRNA COVID-19 Vaccine

by Itzchak Levy, Einav Gal Levin, Liraz Olmer, Gili Regev-Yochay, Nancy Agmon-Levin, Anat Wieder-Finesod, Victoria Indenbaum, Karin Herzog, Ram Doolman, Keren Asraf, Rebecca Halperin, Yaniv Lustig and Galia Rahav

Vaccines 2022, 10(8), 1220; https://doi.org/10.3390/vaccines10081220 - 30 Jul 2022

Cited by 19 | Viewed by 3130

Abstract

Objectives: The BNT162b2 mRNA COVID-19 vaccine has been found to be highly effective in preventing COVID-19 but is associated with increased reactogenicity. We aimed to examine the correlation between immunogenicity and reactogenicity of the BNT162b2 vaccine. Methods: Subjects without prior SARS-CoV-2 infection that [...] Read more.

Objectives: The BNT162b2 mRNA COVID-19 vaccine has been found to be highly effective in preventing COVID-19 but is associated with increased reactogenicity. We aimed to examine the correlation between immunogenicity and reactogenicity of the BNT162b2 vaccine. Methods: Subjects without prior SARS-CoV-2 infection that participated in active surveillance after being vaccinated with the BNT162b2 vaccine were included. Study participants reported adverse drug reactions (ADRs) through questionnaires administered by text message after receiving each dose of the vaccine. A reactogenicity score was developed based on the type and duration of ADRs. In addition, anti-receptor binding domain (RBD) levels and neutralization assays were performed 7–21 and 7–38 days after the first and second vaccine doses, respectively. Associations between ADRs and antibody levels were assessed by Spearman correlations. Multivariable logistic regression analyses were used to identify factors associated with ADRs. Results: A total of 831 health care workers were included. The mean age was 46.5 years (SD = 11.8) and 75.5% were females. 83.4% and 83.3% had at least one local ADR after the first and second doses, respectively. 33% and 83.2% had at least one systemic ADR after the first and second doses, respectively. Multivariate logistic regression analysis found a significant correlation between ADR score and anti-RBD-IgG titers (r = 0.366; p < 0.0001) after adjustment for age, gender, and days after the second vaccination. High anti-RBD-IgG levels, being younger than 55 and being female, were all correlated with increased rates of ADRs. Conclusion: BNT162b2 mRNA COVID-19 vaccine reactogenicity appears to be correlated with higher post-vaccination antibody levels and is independently associated with younger age and female gender. Full article

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16 pages, 746 KB

Open AccessEditor’s ChoiceReview

COVID-19 Vaccine Booster Strategies for Omicron SARS-CoV-2 Variant: Effectiveness and Future Prospects

by Dorota Zarębska-Michaluk, Chenlin Hu, Michał Brzdęk, Robert Flisiak and Piotr Rzymski

Vaccines 2022, 10(8), 1223; https://doi.org/10.3390/vaccines10081223 - 30 Jul 2022

Cited by 18 | Viewed by 18542

Abstract

In the light of the lack of authorized COVID-19 vaccines adapted to the Omicron variant lineage, the administration of the first and second booster dose is recommended. It remains important to monitor the efficacy of such an approach in order to inform future [...] Read more.

In the light of the lack of authorized COVID-19 vaccines adapted to the Omicron variant lineage, the administration of the first and second booster dose is recommended. It remains important to monitor the efficacy of such an approach in order to inform future preventive strategies. The present paper summarizes the research progress on the effectiveness of the first and second booster doses of COVID-19. It also discusses the potential approach in vaccination strategies that could be undertaken to maintain high levels of protection during the waves of SARS-CoV-2 infections. Although this approach can be based, with some shortcomings, on the first-generation vaccines, other vaccination strategies should be explored, including developing multiple antigen-based (multivariant-adapted) booster doses with enhanced durability of immune protection, e.g., through optimization of the half-life of generated antibodies. Full article

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17 pages, 1850 KB

Open AccessEditor’s ChoiceReview

Safety and Efficacy of Influenza Vaccination in Patients Receiving Immune Checkpoint Inhibitors. Systematic Review with Meta-Analysis

by Maria A. Lopez-Olivo, Valeria Valerio, Aliza R. Karpes Matusevich, Marianela Brizio, Michelle Kwok, Yimin Geng, Maria E. Suarez-Almazor and Ines Colmegna

Vaccines 2022, 10(8), 1195; https://doi.org/10.3390/vaccines10081195 - 27 Jul 2022

Cited by 19 | Viewed by 3096

Abstract

The potential increased risk of immune-related adverse events (irAEs) post-influenza vaccine is a concern in patients receiving immune checkpoint inhibitors (ICI). We conducted a systematic review with meta-analysis of studies reporting the effects of influenza vaccination in patients with cancer during ICI treatment. [...] Read more.

The potential increased risk of immune-related adverse events (irAEs) post-influenza vaccine is a concern in patients receiving immune checkpoint inhibitors (ICI). We conducted a systematic review with meta-analysis of studies reporting the effects of influenza vaccination in patients with cancer during ICI treatment. We searched five electronic databases until 01/2022. Two authors independently selected studies, appraised their quality, and collected data. The primary outcome was the determination of pooled irAE rates. Secondary outcomes included determination of immunogenicity and influenza infection rates and cancer-related outcomes. Nineteen studies (26 publications, n = 4705) were included; 89.5% were observational. Vaccinated patients reported slighter lower rates of irAEs compared to unvaccinated patients (32% versus 41%, respectively). Seroprotection for influenza type A was 78%–79%, and for type B was 75%. Influenza and irAE-related death rates were similar between groups. The pooled proportion of participants reporting a laboratory-confirmed infection was 2% (95% CI 0% to 6%), and influenza-like illness was 14% (95% CI 2% to 32%). No differences were reported on the rates of laboratory-confirmed infection between vaccinated and unvaccinated patients. Longer progression-free and overall survival was also observed in vaccinated compared with unvaccinated patients. Current evidence suggests that influenza vaccination is safe in patients receiving ICIs, does not increase the risk of irAEs, and may improve survival. Full article

(This article belongs to the Section Influenza Virus Vaccines)

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27 pages, 1796 KB

Open AccessEditor’s ChoiceReview

Nanoparticle- and Microparticle-Based Vaccines against Orbiviruses of Veterinary Importance

by Luis Jiménez-Cabello, Sergio Utrilla-Trigo, Natalia Barreiro-Piñeiro, Tomás Pose-Boirazian, José Martínez-Costas, Alejandro Marín-López and Javier Ortego

Vaccines 2022, 10(7), 1124; https://doi.org/10.3390/vaccines10071124 - 14 Jul 2022

Cited by 11 | Viewed by 4857

Abstract

Bluetongue virus (BTV) and African horse sickness virus (AHSV) are widespread arboviruses that cause important economic losses in the livestock and equine industries, respectively. In addition to these, another arthropod-transmitted orbivirus known as epizootic hemorrhagic disease virus (EHDV) entails a major threat as [...] Read more.

Bluetongue virus (BTV) and African horse sickness virus (AHSV) are widespread arboviruses that cause important economic losses in the livestock and equine industries, respectively. In addition to these, another arthropod-transmitted orbivirus known as epizootic hemorrhagic disease virus (EHDV) entails a major threat as there is a conducive landscape that nurtures its emergence in non-endemic countries. To date, only vaccinations with live attenuated or inactivated vaccines permit the control of these three viral diseases, although important drawbacks, e.g., low safety profile and effectiveness, and lack of DIVA (differentiation of infected from vaccinated animals) properties, constrain their usage as prophylactic measures. Moreover, a substantial number of serotypes of BTV, AHSV and EHDV have been described, with poor induction of cross-protective immune responses among serotypes. In the context of next-generation vaccine development, antigen delivery systems based on nano- or microparticles have gathered significant attention during the last few decades. A diversity of technologies, such as virus-like particles or self-assembled protein complexes, have been implemented for vaccine design against these viruses. In this work, we offer a comprehensive review of the nano- and microparticulated vaccine candidates against these three relevant orbiviruses. Additionally, we also review an innovative technology for antigen delivery based on the avian reovirus nonstructural protein muNS and we explore the prospective functionality of the nonstructural protein NS1 nanotubules as a BTV-based delivery platform. Full article

(This article belongs to the Special Issue Microparticle-Based Vaccines)

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18 pages, 1381 KB

Open AccessEditor’s ChoiceReview

Pseudomonas aeruginosa: Recent Advances in Vaccine Development

by Matthew Killough, Aoife Maria Rodgers and Rebecca Jo Ingram

Vaccines 2022, 10(7), 1100; https://doi.org/10.3390/vaccines10071100 - 8 Jul 2022

Cited by 50 | Viewed by 18475

Abstract

Pseudomonas aeruginosa is an important opportunistic human pathogen. Using its arsenal of virulence factors and its intrinsic ability to adapt to new environments, P. aeruginosa causes a range of complicated acute and chronic infections in immunocompromised individuals. Of particular importance are burn wound [...] Read more.

Pseudomonas aeruginosa is an important opportunistic human pathogen. Using its arsenal of virulence factors and its intrinsic ability to adapt to new environments, P. aeruginosa causes a range of complicated acute and chronic infections in immunocompromised individuals. Of particular importance are burn wound infections, ventilator-associated pneumonia, and chronic infections in people with cystic fibrosis. Antibiotic resistance has rendered many of these infections challenging to treat and novel therapeutic strategies are limited. Multiple clinical studies using well-characterised virulence factors as vaccine antigens over the last 50 years have fallen short, resulting in no effective vaccination being available for clinical use. Nonetheless, progress has been made in preclinical research, namely, in the realms of antigen discovery, adjuvant use, and novel delivery systems. Herein, we briefly review the scope of P. aeruginosa clinical infections and its major important virulence factors. Full article

(This article belongs to the Section Vaccines against Tropical and other Infectious Diseases)

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16 pages, 1433 KB

Open AccessEditor’s ChoiceArticle

Correlates of Zero-Dose Vaccination Status among Children Aged 12–59 Months in Sub-Saharan Africa: A Multilevel Analysis of Individual and Contextual Factors

by Chamberline E. Ozigbu, Bankole Olatosi, Zhenlong Li, James W. Hardin and Nicole L. Hair

Vaccines 2022, 10(7), 1052; https://doi.org/10.3390/vaccines10071052 - 30 Jun 2022

Cited by 22 | Viewed by 4512

Abstract

Despite ongoing efforts to improve childhood vaccination coverage, including in hard-to-reach and hard-to-vaccinate communities, many children in sub-Saharan Africa (SSA) remain unvaccinated. Considering recent goals set by the Immunization Agenda 2030 (IA2030), including reducing the number of zero-dose children by half, research that [...] Read more.

Despite ongoing efforts to improve childhood vaccination coverage, including in hard-to-reach and hard-to-vaccinate communities, many children in sub-Saharan Africa (SSA) remain unvaccinated. Considering recent goals set by the Immunization Agenda 2030 (IA2030), including reducing the number of zero-dose children by half, research that goes beyond coverage to identify populations and groups at greater risk of being unvaccinated is urgently needed. This is a pooled cross-sectional study of individual- and country-level data obtained from Demographic and Health Surveys Program and two open data repositories. The sample includes 43,131 children aged 12–59 months sampled between 2010 and 2020 in 33 SSA countries. Associations of zero-dose status with individual and contextual factors were assessed using multilevel logistic regression. 16.5% of children had not received any vaccines. Individual level factors associated lower odds of zero-dose status included mother’s primary school or high school education, employment, use of antenatal care services and household wealth. Compared to children in countries with lower GDP, children in countries with relatively high GDP had nearly four times greater odds of being unvaccinated. Both individual and contextual factors are correlated with zero-dose status in SSA. Our results can inform efforts to identify and reach children who have not received any vaccines. Full article

(This article belongs to the Special Issue Immunization of Children and Women against Infectious Diseases)

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15 pages, 2305 KB

Open AccessEditor’s ChoiceArticle

A Cloned Recombinant Vesicular Stomatitis Virus-Vectored Marburg Vaccine, PHV01, Protects Guinea Pigs from Lethal Marburg Virus Disease

by Wenjun Zhu, Guodong Liu, Wenguang Cao, Shihua He, Anders Leung, Ute Ströher, Michael J. Fairchild, Rick Nichols, Joseph Crowell, Joan Fusco and Logan Banadyga

Vaccines 2022, 10(7), 1004; https://doi.org/10.3390/vaccines10071004 - 23 Jun 2022

Cited by 15 | Viewed by 3467

Abstract

Marburg virus (MARV) is a negative-sense, single-stranded RNA virus that belongs to the Filoviridae family. Despite having caused numerous outbreaks of severe hemorrhagic fever with high case fatality rates, there are still no clinically approved therapeutics or vaccines to treat or prevent MARV [...] Read more.

Marburg virus (MARV) is a negative-sense, single-stranded RNA virus that belongs to the Filoviridae family. Despite having caused numerous outbreaks of severe hemorrhagic fever with high case fatality rates, there are still no clinically approved therapeutics or vaccines to treat or prevent MARV disease. Recombinant vesicular stomatitis viruses (rVSVs) expressing heterologous viral glycoproteins have shown remarkable promise as live-attenuated vaccine vectors, with an rVSV-based Ebola virus vaccine having received regulatory approval in the United States and numerous other countries. Analogous rVSV vaccine vectors have also been developed for MARV and have shown efficacy in several preclinical studies conducted in nonhuman primates. Here, we used a guinea pig model to confirm the protective efficacy of a cloned, rVSV-based candidate vaccine, termed PHV01, expressing the MARV variant Angola glycoprotein. Our results demonstrated that a single dose (2 × 10⁶ PFU) of vaccine administered 28 days prior to challenge with a uniformly lethal dose of guinea-pig-adapted MARV variant Angola provided complete protection from death and disease. Moreover, protection was robust, with as little as 200 PFU of vaccine conferring significant protection. Not only does this study highlight the potential predictive value of the guinea pig model in the evaluation of MARV countermeasures, but it also demonstrates consistent and reproducible protection afforded by a clonal vaccine candidate. Indeed, this study identifies PHV01 as a suitable vaccine candidate for advanced development. Full article

(This article belongs to the Special Issue Vaccine Development Needs for Marburg Virus and Sudan Ebolavirus: Leveraging Lessons Learned from the Zaire Ebolavirus)

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19 pages, 373 KB

Open AccessEditor’s ChoiceReview

Vaccine Preventable Zoonotic Diseases: Challenges and Opportunities for Public Health Progress

by Ann Carpenter, Michelle A. Waltenburg, Aron Hall, James Kile, Marie Killerby, Barbara Knust, Maria Negron, Megin Nichols, Ryan M. Wallace, Casey Barton Behravesh, Jennifer H. McQuiston and the Vaccine Preventable Zoonotic Disease Working Group

Vaccines 2022, 10(7), 993; https://doi.org/10.3390/vaccines10070993 - 22 Jun 2022

Cited by 37 | Viewed by 9235

Abstract

Zoonotic diseases represent a heavy global burden, causing important economic losses, impacting animal health and production, and costing millions of human lives. The vaccination of animals and humans to prevent inter-species zoonotic disease transmission is an important intervention. However, efforts to develop and [...] Read more.

Zoonotic diseases represent a heavy global burden, causing important economic losses, impacting animal health and production, and costing millions of human lives. The vaccination of animals and humans to prevent inter-species zoonotic disease transmission is an important intervention. However, efforts to develop and implement vaccine interventions to reduce zoonotic disease impacts are often limited to the veterinary and agricultural sectors and do not reflect the shared burden of disease. Multisectoral collaboration, including co-development opportunities for human and animal vaccines, expanding vaccine use to include animal reservoirs such as wildlife, and strategically using vaccines to interrupt complex transmission cycles is needed. Addressing zoonoses requires a multi-faceted One Health approach, wherein vaccinating people and animals plays a critical role. Full article

(This article belongs to the Special Issue Veterinary Vaccines and One Health)

15 pages, 1010 KB

Open AccessEditor’s ChoiceArticle

Predictors of Immunogenic Response to the BNT162b2 mRNA COVID-19 Vaccination in Patients with Autoimmune Inflammatory Rheumatic Diseases Treated with Rituximab

by Victoria Furer, Tali Eviatar, Devy Zisman, Hagit Peleg, Yolanda Braun-Moscovici, Alexandra Balbir-Gurman, Daphna Paran, David Levartovsky, Michael Zisapel, Ofir Elalouf, Ilana Kaufman, Adi Broyde, Ari Polachek, Joy Feld, Amir Haddad, Tal Gazitt, Muna Elias, Nizar Higazi, Fadi Kharouf, Sara Pel, Sharon Nevo and Ori Elkayam Show full author list Hide full author list

Vaccines 2022, 10(6), 901; https://doi.org/10.3390/vaccines10060901 - 6 Jun 2022

Cited by 23 | Viewed by 3354

Abstract

Treatment with rituximab (RTX) blunts SARS-CoV-2 vaccination-induced humoral response. We sought to identify predictors of a positive immunogenic response to the BNT162b2 mRNA vaccine in patients with autoimmune inflammatory rheumatic diseases (AIIRD) treated with RTX (AIIRD-RTX). We analyzed 108 AIIRD-RTX patients and 122 [...] Read more.

Treatment with rituximab (RTX) blunts SARS-CoV-2 vaccination-induced humoral response. We sought to identify predictors of a positive immunogenic response to the BNT162b2 mRNA vaccine in patients with autoimmune inflammatory rheumatic diseases (AIIRD) treated with RTX (AIIRD-RTX). We analyzed 108 AIIRD-RTX patients and 122 immunocompetent controls vaccinated with BNT162b2 mRNA participating in a multicenter vaccination study. Immunogenicity was defined by positive anti-SARS-CoV-2 S1/S2 IgG. We used a stepwise backward multiple logistic regression to identify predicting factors for a positive immunogenic response to vaccination and develop a predicting calculator, further validated in an independent cohort of AIIRD-RTX BNT162b2 mRNA vaccinated patients (n = 48). AIIRD-RTX patients who mounted a seropositive immunogenic response significantly differed from patients who did not by a lower number of RTX courses (median (range) 3 (1–10) vs. 5 (1–15), p = 0.007; lower cumulative RTX dose (mean ± SD) 6943.11 ± 5975.74 vs. 9780.95 ± 7240.12 mg, p = 0.033; higher IgG level prior to last RTX course (mean ± SD), 1189.78 ± 576.28 vs. 884.33 ± 302.31 mg/dL, p = 0.002), and extended interval between RTX treatment and vaccination, 469.82 ± 570.39 vs. 162.08 ± 160.12 days, p = 0.0009, respectively. Patients with ANCA-associated vasculitis and inflammatory myositis had a low likelihood of a seropositive immunogenic response compared to patients with rheumatoid arthritis, odds ratio (OR) 0.209, 95% confidence interval (CI) 0.046–0.96, p = 0.044 and OR 0.189, 95% CI 0.036–0.987, p = 0.048, respectively. Based on these findings, we constructed a calculator predicting the probability of a seropositive immunogenic response following BNT162b2 mRNA vaccination which performed with 90.5% sensitivity, 59.3% specificity, and 63.3% positive and 88.9% negative predictive values. In summary, the predicting calculator could guide clinicians for optimal timing of BNT162b2 mRNA vaccination in AIIRD-RTX patients. Full article

(This article belongs to the Topic Global Analysis of SARS-CoV-2 Serology)

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26 pages, 748 KB

Open AccessEditor’s ChoiceReview

An Overview of Vaccine Adjuvants: Current Evidence and Future Perspectives

by Alessio Facciolà, Giuseppa Visalli, Antonio Laganà and Angela Di Pietro

Vaccines 2022, 10(5), 819; https://doi.org/10.3390/vaccines10050819 - 22 May 2022

Cited by 194 | Viewed by 29568

Abstract

Vaccinations are one of the most important preventive tools against infectious diseases. Over time, many different types of vaccines have been developed concerning the antigen component. Adjuvants are essential elements that increase the efficacy of vaccination practises through many different actions, especially acting [...] Read more.

Vaccinations are one of the most important preventive tools against infectious diseases. Over time, many different types of vaccines have been developed concerning the antigen component. Adjuvants are essential elements that increase the efficacy of vaccination practises through many different actions, especially acting as carriers, depots, and stimulators of immune responses. For many years, few adjuvants have been included in vaccines, with aluminium salts being the most commonly used adjuvant. However, recent research has focused its attention on many different new compounds with effective adjuvant properties and improved safety. Modern technologies such as nanotechnologies and molecular biology have forcefully entered the production processes of both antigen and adjuvant components, thereby improving vaccine efficacy. Microparticles, emulsions, and immune stimulators are currently in the spotlight for their huge potential in vaccine production. Although studies have reported some potential side effects of vaccine adjuvants such as the recently recognised ASIA syndrome, the huge worth of vaccines remains unquestionable. Indeed, the recent COVID-19 pandemic has highlighted the importance of vaccines, especially in regard to managing future potential pandemics. In this field, research into adjuvants could play a leading role in the production of increasingly effective vaccines. Full article

(This article belongs to the Special Issue Present and Future Vaccinations: Current Strategies and New Perspectives in the Fight against Infectious Diseases)

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17 pages, 285 KB

Open AccessEditor’s ChoiceReview

Vaccination for the Prevention of Infection among Immunocompromised Patients: A Concise Review of Recent Systematic Reviews

by Kay Choong See

Vaccines 2022, 10(5), 800; https://doi.org/10.3390/vaccines10050800 - 18 May 2022

Cited by 38 | Viewed by 5457

Abstract

Vaccination is crucial for avoiding infection-associated morbidity and mortality among immunocompromised patients. However, immunocompromised patients respond less well to vaccinations compared to healthy people, and little is known about the relative efficacy of various vaccines among different immunocompromised states. A total of 54 [...] Read more.

Vaccination is crucial for avoiding infection-associated morbidity and mortality among immunocompromised patients. However, immunocompromised patients respond less well to vaccinations compared to healthy people, and little is known about the relative efficacy of various vaccines among different immunocompromised states. A total of 54 systematic reviews (22 COVID-19; 32 non-COVID-19) published within the last 5 years in Pubmed^® were reviewed. They demonstrated similar patterns within three seroconversion response categories: good (about >60% when compared to healthy controls), intermediate (~40–60%), and poor (about <40%). Good vaccine responses would be expected for patients with chronic kidney disease, human immunodeficiency virus infection (normal CD4 counts), immune-mediated inflammatory diseases, post-splenectomy states, and solid tumors. Intermediate vaccine responses would be expected for patients with anti-cytotoxic T-lymphocyte antigen-4 therapy, hematologic cancer, and human immunodeficiency virus infection (low CD4 counts). Poor vaccine responses would be expected for patients with B-cell-depleting agents (e.g., anti-CD20 therapy), hematopoietic stem-cell transplant, solid organ transplant, and liver cirrhosis. For all vaccine response categories, vaccination should be timed when patients are least immunosuppressed. For the intermediate and poor vaccine response categories, high-dose vaccine, revaccination when patients are less immunosuppressed, checking for seroconversion, additional booster doses, and long-acting monoclonal antibodies may be considered, supplemented by shielding measures. Full article

(This article belongs to the Special Issue Vaccines for Patients With Immunodeficiencies and Their Efficacy: An Overview in Pandemic Era)

16 pages, 1425 KB

Open AccessEditor’s ChoiceReview

The Global Impact of Hepatitis B Vaccination on Hepatocellular Carcinoma

by Joan Ericka Flores, Alexander J. Thompson, Marno Ryan and Jessica Howell

Vaccines 2022, 10(5), 793; https://doi.org/10.3390/vaccines10050793 - 17 May 2022

Cited by 54 | Viewed by 7229

Abstract

Over 1.5 million preventable new hepatitis B infections continue to occur each year and there are an estimated 296 million people living with chronic hepatitis B infection worldwide, resulting in more than 820,000 deaths annually due to liver cirrhosis and hepatocellular carcinoma (HCC). [...] Read more.

Over 1.5 million preventable new hepatitis B infections continue to occur each year and there are an estimated 296 million people living with chronic hepatitis B infection worldwide, resulting in more than 820,000 deaths annually due to liver cirrhosis and hepatocellular carcinoma (HCC). Hepatitis B vaccination remains the cornerstone of public health policy to prevent HCC and a vital component of the global hepatitis B elimination response. The WHO has set a 90% vaccination target to achieve hepatitis B elimination by 2030; however, there is wide variability in reported birth dose coverage, with global coverage at only 42%. In this review, we outline the global trends in hepatitis B vaccination coverage and the impact of hepatitis B vaccination on HCC incidence and discuss the challenges and enabling factors for achieving WHO 2030 hepatitis B vaccination coverage targets. Full article

(This article belongs to the Special Issue Hepatitis and Vaccines)

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11 pages, 852 KB

Open AccessEditor’s ChoiceReview

Uptake of COVID-19 Vaccines among Pregnant Women: A Systematic Review and Meta-Analysis

by Petros Galanis, Irene Vraka, Olga Siskou, Olympia Konstantakopoulou, Aglaia Katsiroumpa and Daphne Kaitelidou

Vaccines 2022, 10(5), 766; https://doi.org/10.3390/vaccines10050766 - 12 May 2022

Cited by 82 | Viewed by 5896

Abstract

Mass vaccination against COVID-19 is essential to control the pandemic. COVID-19 vaccines are now recommended during pregnancy to prevent adverse outcomes. With this review, we aimed to evaluate the evidence in the literature regarding the uptake of COVID-19 vaccinations among pregnant women. A [...] Read more.

Mass vaccination against COVID-19 is essential to control the pandemic. COVID-19 vaccines are now recommended during pregnancy to prevent adverse outcomes. With this review, we aimed to evaluate the evidence in the literature regarding the uptake of COVID-19 vaccinations among pregnant women. A comprehensive search was performed in PubMed, Medline, Scopus, ProQuest, Web of Science, CINAHL, and medRxiv from inception to 23 March 2022. We performed a meta-analysis to estimate the overall proportion of pregnant women vaccinated against COVID-19. We found 11 studies including 703,004 pregnant women. The overall proportion of pregnant women vaccinated against COVID-19 was 27.5% (95% CI: 18.8–37.0%). Predictors of COVID-19 vaccination uptake were older age, ethnicity, race, trust in COVID-19 vaccines, and fear of COVID-19 during pregnancy. Mistrust in the government, diagnosis of COVID-19 during pregnancy, and fears about the safety and side effects of COVID-19 vaccines were reasons for declining vaccination. The global COVID-19 vaccination prevalence in pregnant women is low. A large gap exists in the literature on the factors influencing the decision of pregnant women to be vaccinated against COVID-19. Targeted information campaigns are essential to increase vaccine literacy among pregnant women. Full article

(This article belongs to the Special Issue People’s Perception on COVID-19 Vaccine and Its Accessibility)

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33 pages, 1784 KB

Open AccessEditor’s ChoiceReview

Vaccination against Bacterial Infections: Challenges, Progress, and New Approaches with a Focus on Intracellular Bacteria

by Anke Osterloh

Vaccines 2022, 10(5), 751; https://doi.org/10.3390/vaccines10050751 - 10 May 2022

Cited by 31 | Viewed by 9112

Abstract

Many bacterial infections are major health problems worldwide, and treatment of many of these infectious diseases is becoming increasingly difficult due to the development of antibiotic resistance, which is a major threat. Prophylactic vaccines against these bacterial pathogens are urgently needed. This is [...] Read more.

Many bacterial infections are major health problems worldwide, and treatment of many of these infectious diseases is becoming increasingly difficult due to the development of antibiotic resistance, which is a major threat. Prophylactic vaccines against these bacterial pathogens are urgently needed. This is also true for bacterial infections that are still neglected, even though they affect a large part of the world’s population, especially under poor hygienic conditions. One example is typhus, a life-threatening disease also known as “war plague” caused by Rickettsia prowazekii, which could potentially come back in a war situation such as the one in Ukraine. However, vaccination against bacterial infections is a challenge. In general, bacteria are much more complex organisms than viruses and as such are more difficult targets. Unlike comparatively simple viruses, bacteria possess a variety of antigens whose immunogenic potential is often unknown, and it is unclear which antigen can elicit a protective and long-lasting immune response. Several vaccines against extracellular bacteria have been developed in the past and are still used successfully today, e.g., vaccines against tetanus, pertussis, and diphtheria. However, while induction of antibody production is usually sufficient for protection against extracellular bacteria, vaccination against intracellular bacteria is much more difficult because effective defense against these pathogens requires T cell-mediated responses, particularly the activation of cytotoxic CD8⁺ T cells. These responses are usually not efficiently elicited by immunization with non-living whole cell antigens or subunit vaccines, so that other antigen delivery strategies are required. This review provides an overview of existing antibacterial vaccines and novel approaches to vaccination with a focus on immunization against intracellular bacteria. Full article

(This article belongs to the Special Issue Immunity and Vaccination against Bacterial Infections)

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13 pages, 2207 KB

Open AccessEditor’s ChoiceArticle

Internal and External Motivations and Risk Perception toward COVID-19 Vaccination in Adolescents in the U.S.

by Pikuei Tu, Michaela Kotarba, Brooke Bier, Rachel Clark and Cheryl Lin

Vaccines 2022, 10(5), 697; https://doi.org/10.3390/vaccines10050697 - 29 Apr 2022

Cited by 20 | Viewed by 3552

Abstract

The COVID-19 vaccine is widely available to adolescents in the U.S.; however, vaccine hesitancy poses a threat to full coverage. The literature shows that perceived risks and the presence or lack of motivators are determinants for vaccination decisions, yet research evidence from minors [...] Read more.

The COVID-19 vaccine is widely available to adolescents in the U.S.; however, vaccine hesitancy poses a threat to full coverage. The literature shows that perceived risks and the presence or lack of motivators are determinants for vaccination decisions, yet research evidence from minors is scant. This study adopted the Protection Motivation framework to identify differences in these facilitators and compare the influence of internal and external motivators among American adolescents in COVID-19 vaccine uptake. A nationwide online survey analyzed 13–17-year-old teenagers’ COVID-19 beliefs as well as present or potential reasons for accepting the vaccine. Of the 439 participants, 21.18% were not and did not plan to get vaccinated. Another 52.39% had at least one dosage, of which over three-quarters were internally motivated (whereas those unvaccinated were more likely to be externally motivated, X² = 4.117, p = 0.042). In unvaccinated individuals, older adolescents reported slightly more internal motivators than younger adolescents (t = −2.023, p = 0.046). Internal motivation was associated with higher risk perception (r² = 0.06651, p = 0.001), but risk perception had a stronger relationship with vaccination status (r² = 0.1816, p < 0.001), with vaccinated individuals showing higher risk perception than those unvaccinated (mean difference = 0.42 on a scale of 1–4; t = −3.603, p < 0.001); the risk perception difference was even greater between hesitant and non-hesitant participants (mean difference = 0.63; t = −0.892, p < 0.001). The relationship was moderated by perceived knowledge, where the difference in risk perception between vaccination status was only significant for those with low perceived knowledge (f = 10.59, p = 0.001). Increasing awareness of disease risks and stressing internal motivators may be key to improving uptake in young people. Future research could delve deeper into risk perception formation of adolescents and why and how it differs across populations. Full article

(This article belongs to the Special Issue Feature Papers of Vaccines and Society)

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25 pages, 1469 KB

Open AccessEditor’s ChoiceReview

Cell Lines for the Development of African Swine Fever Virus Vaccine Candidates: An Update

by Dionigia Meloni, Giulia Franzoni and Annalisa Oggiano

Vaccines 2022, 10(5), 707; https://doi.org/10.3390/vaccines10050707 - 29 Apr 2022

Cited by 29 | Viewed by 5786

Abstract

African swine fever virus (ASFV) is the etiological agent of a highly lethal disease in both domestic and wild pigs. The virus has rapidly spread worldwide and has no available licensed vaccine. An obstacle to the construction of a safe and efficient vaccine [...] Read more.

African swine fever virus (ASFV) is the etiological agent of a highly lethal disease in both domestic and wild pigs. The virus has rapidly spread worldwide and has no available licensed vaccine. An obstacle to the construction of a safe and efficient vaccine is the lack of a suitable cell line for ASFV isolation and propagation. Macrophages are the main targets for ASFV, and they have been widely used to study virus–host interactions; nevertheless, obtaining these cells is time-consuming and expensive, and they are not ethically suitable for the production of large-scale vaccines. To overcome these issues, different virulent field isolates have been adapted on monkey or human continuous cells lines; however, several culture passages often lead to significant genetic modifications and the loss of immunogenicity of the adapted strain. Thus, several groups have attempted to establish a porcine cell line able to sustain ASFV growth. Preliminary data suggested that some porcine continuous cell lines might be an alternative to primary macrophages for ASFV research and for large-scale vaccine production, although further studies are still needed. In this review, we summarize the research to investigate the most suitable cell line for ASFV isolation and propagation. Full article

(This article belongs to the Special Issue African Swine Fever Immunity and Vaccines)

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14 pages, 657 KB

Open AccessEditor’s ChoiceArticle

COVID-19 Vaccination in Multiple Sclerosis and Inflammatory Diseases: Effects from Disease-Modifying Therapy, Long-Term Seroprevalence and Breakthrough Infections

by Dejan Jakimovski, Karen Zakalik, Samreen Awan, Katelyn S. Kavak, Penny Pennington, David Hojnacki, Channa Kolb, Alexis A. Lizarraga, Svetlana P. Eckert, Rosila Sarrosa, Kamath Vineetha, Keith Edwards and Bianca Weinstock-Guttman

Vaccines 2022, 10(5), 695; https://doi.org/10.3390/vaccines10050695 - 28 Apr 2022

Cited by 22 | Viewed by 4430

Abstract

Background: To determine the effect of disease-modifying therapies (DMT) on humoral postvaccine seroconversion, long-term humoral response, and breakthrough COVID-19 infections in persons with multiple sclerosis (PwMS) and other neuroinflammatory disorders. Methods: A total of 757 PwMS and other neuroinflammatory disorders were recruited in [...] Read more.

Background: To determine the effect of disease-modifying therapies (DMT) on humoral postvaccine seroconversion, long-term humoral response, and breakthrough COVID-19 infections in persons with multiple sclerosis (PwMS) and other neuroinflammatory disorders. Methods: A total of 757 PwMS and other neuroinflammatory disorders were recruited in two MS centers and vaccinated with one of the FDA-approved vaccines (BNT162b2, mRNA-1273, Ad26.COV2.S). The primary outcomes are the rate of humoral postvaccine seroconversion and anti-severe acute respiratory syndrome coronavirus 2 (anti-SARS-CoV-2) immunoglobulin G (IgG) differences between patients on different DMTs. Secondary measures include breakthrough infections and humoral response after six months. Other outcomes include differences in vaccine response between SARS-CoV-2 vaccines and the effects of age and comorbidities on the vaccine response. Results: A total of 465 (68.4%) PwMS and 55 (74.3%) patients with neuroinflammatory diseases were seropositive at 4–12 weeks after vaccination. A significant difference in seroconversion based on the DMT used at the time of vaccination (p < 0.001) was observed, with the lowest rates seen in patients treated with anti-CD20 antibodies (23.2%) and sphingosine-1-phosphate modulators (S1P) (30.8%). In seropositive patients, there was a significant decrease in anti-SARS IgG from mean 20.0 to 4.7 at six months (p = 0.004). Thirty-nine patients had breakthrough infection, but only two seronegative patients required hospitalization. mRNA vaccines resulted in significantly greater seroconversion compared to Ad26.COV2.S (p < 0.001). Older age and presence of cardiovascular comorbidities were associated with lower anti-SARS IgG (p = 0.021 and p = 0.003, respectively) Conclusions: PwMS and neuroinflammatory disorders treated with anti-CD20 and S1P medications have lower humoral response after anti-SARS-CoV-2 vaccination, even after booster dose. Waning of the humoral response puts vaccinated PwMS at a greater risk of COVID-19 breakthrough. Full article

(This article belongs to the Special Issue Vaccine-Induced Reprogramming of Innate Immune Response)

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22 pages, 1334 KB

Open AccessEditor’s ChoiceReview

Immunosenescence and Altered Vaccine Efficiency in Older Subjects: A Myth Difficult to Change

by Tamas Fulop, Anis Larbi, Graham Pawelec, Alan A. Cohen, Guillaume Provost, Abedelouahed Khalil, Guy Lacombe, Serafim Rodrigues, Mathieu Desroches, Katsuiku Hirokawa, Claudio Franceschi and Jacek M. Witkowski

Vaccines 2022, 10(4), 607; https://doi.org/10.3390/vaccines10040607 - 13 Apr 2022

Cited by 29 | Viewed by 7399

Abstract

Organismal ageing is associated with many physiological changes, including differences in the immune system of most animals. These differences are often considered to be a key cause of age-associated diseases as well as decreased vaccine responses in humans. The most often cited vaccine [...] Read more.

Organismal ageing is associated with many physiological changes, including differences in the immune system of most animals. These differences are often considered to be a key cause of age-associated diseases as well as decreased vaccine responses in humans. The most often cited vaccine failure is seasonal influenza, but, while it is usually the case that the efficiency of this vaccine is lower in older than younger adults, this is not always true, and the reasons for the differential responses are manifold. Undoubtedly, changes in the innate and adaptive immune response with ageing are associated with failure to respond to the influenza vaccine, but the cause is unclear. Moreover, recent advances in vaccine formulations and adjuvants, as well as in our understanding of immune changes with ageing, have contributed to the development of vaccines, such as those against herpes zoster and SARS-CoV-2, that can protect against serious disease in older adults just as well as in younger people. In the present article, we discuss the reasons why it is a myth that vaccines inevitably protect less well in older individuals, and that vaccines represent one of the most powerful means to protect the health and ensure the quality of life of older adults. Full article

(This article belongs to the Special Issue Knowledge about Vaccines and Vaccination in Older People)

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28 pages, 2249 KB

Open AccessEditor’s ChoiceReview

COVID-19 Vaccines: Current and Future Perspectives

by Luca Soraci, Fabrizia Lattanzio, Giulia Soraci, Maria Elsa Gambuzza, Claudio Pulvirenti, Annalisa Cozza, Andrea Corsonello, Filippo Luciani and Giovanni Rezza

Vaccines 2022, 10(4), 608; https://doi.org/10.3390/vaccines10040608 - 13 Apr 2022

Cited by 38 | Viewed by 9118

Abstract

Currently available vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are highly effective but not able to keep the coronavirus disease 2019 (COVID-19) pandemic completely under control. Alternative R&D strategies are required to induce a long-lasting immunological response and to reduce adverse events [...] Read more.

Currently available vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are highly effective but not able to keep the coronavirus disease 2019 (COVID-19) pandemic completely under control. Alternative R&D strategies are required to induce a long-lasting immunological response and to reduce adverse events as well as to favor rapid development and large-scale production. Several technological platforms have been used to develop COVID-19 vaccines, including inactivated viruses, recombinant proteins, DNA- and RNA-based vaccines, virus-vectored vaccines, and virus-like particles. In general, mRNA vaccines, protein-based vaccines, and vectored vaccines have shown a high level of protection against COVID-19. However, the mutation-prone nature of the spike (S) protein affects long-lasting vaccine protection and its effectiveness, and vaccinated people can become infected with new variants, also showing high virus levels. In addition, adverse effects may occur, some of them related to the interaction of the S protein with the angiotensin-converting enzyme 2 (ACE-2). Thus, there are some concerns that need to be addressed and challenges regarding logistic problems, such as strict storage at low temperatures for some vaccines. In this review, we discuss the limits of vaccines developed against COVID-19 and possible innovative approaches. Full article

(This article belongs to the Special Issue Vaccination Strategies for COVID-19)

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23 pages, 2505 KB

Open AccessEditor’s ChoiceArticle

Protective CD8+ T Cell Response Induced by Modified Vaccinia Virus Ankara Delivering Ebola Virus Nucleoprotein

by Alexandra Kupke, Asisa Volz, Erik Dietzel, Astrid Freudenstein, Jörg Schmidt, Hosam Shams-Eldin, Sylvia Jany, Lucie Sauerhering, Verena Krähling, Michelle Gellhorn Serra, Christiane Herden, Markus Eickmann, Stephan Becker and Gerd Sutter

Vaccines 2022, 10(4), 533; https://doi.org/10.3390/vaccines10040533 - 29 Mar 2022

Cited by 11 | Viewed by 4127

Abstract

The urgent need for vaccines against Ebola virus (EBOV) was underscored by the large outbreak in West Africa (2014–2016). Since then, several promising vaccine candidates have been tested in pre-clinical and clinical studies. As a result, two vaccines were approved for human use [...] Read more.

The urgent need for vaccines against Ebola virus (EBOV) was underscored by the large outbreak in West Africa (2014–2016). Since then, several promising vaccine candidates have been tested in pre-clinical and clinical studies. As a result, two vaccines were approved for human use in 2019/2020, of which one includes a heterologous adenovirus/Modified Vaccinia virus Ankara (MVA) prime-boost regimen. Here, we tested new vaccine candidates based on the recombinant MVA vector, encoding the EBOV nucleoprotein (MVA-EBOV-NP) or glycoprotein (MVA-EBOV-GP) for their efficacy after homologous prime-boost immunization in mice. Our aim was to investigate the role of each antigen in terms of efficacy and correlates of protection. Sera of mice vaccinated with MVA-EBOV-GP were virus-neutralizing and MVA-EBOV-NP immunization readily elicited interferon-γ-producing NP-specific CD8+ T cells. While mock-vaccinated mice succumbed to EBOV infection, all vaccinated mice survived and showed drastically decreased viral loads in sera and organs. In addition, MVA-EBOV-NP vaccinated mice became susceptible to lethal EBOV infection after depletion of CD8+ T cells prior to challenge. This study highlights the potential of MVA-based vaccines to elicit humoral immune responses as well as a strong and protective CD8+ T cell response and contributes to understanding the possible underlying mechanisms. Full article

(This article belongs to the Special Issue A Modern Take on Replicating Viral Vaccines)

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10 pages, 916 KB

Open AccessEditor’s ChoiceArticle

Humoral Response after Three Doses of mRNA-1273 or BNT162b2 SARS-CoV-2 Vaccines in Hemodialysis Patients

by José Jesús Broseta, Diana Rodríguez-Espinosa, Elena Cuadrado, Néstor Rodríguez, José Luis Bedini and Francisco Maduell

Vaccines 2022, 10(4), 522; https://doi.org/10.3390/vaccines10040522 - 27 Mar 2022

Cited by 13 | Viewed by 3625

Abstract

The COVID-19 pandemic continues to be a worldwide health issue. Among hemodialysis (HD) patients, two-dose immunization schemes with mRNA vaccines have contributed to preventing severe COVID-19 cases; however, some have not produced a sufficient humoral response, and most have developed a rapid decline [...] Read more.

The COVID-19 pandemic continues to be a worldwide health issue. Among hemodialysis (HD) patients, two-dose immunization schemes with mRNA vaccines have contributed to preventing severe COVID-19 cases; however, some have not produced a sufficient humoral response, and most have developed a rapid decline in antibody levels over the months following vaccination. This observational, prospective, multi-center study evaluated the humoral response in terms of presence and levels of IgG antibodies to the receptor-binding domain of the S1 spike antigen of SARS-CoV-2 (anti-S1-RBD IgG) to the third dose of SARS-CoV-2 mRNA vaccines, either the mRNA-1273 (Moderna) or BNT162b2 (Pfizer), in 153 patients from three dialysis units affiliated to Hospital Clínic of Barcelona (Spain). Most hemodialysis patients responded intensely to this third vaccine dose, achieving the seroconversion in three out of four non- or weak responders to two doses. Moreover, 96.1% maintained the upper limit or generated higher titers than after the second. BNT162b2 vaccine, active cancer, and immunosuppressive treatment were related to a worse humoral response. Every hemodialysis patient should be administered a third vaccine dose six months after receiving the second one. Despite the lack of data, immunosuppressed patients and those with active cancer may benefit from more frequent vaccine boosters. Full article

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21 pages, 6487 KB

Open AccessEditor’s ChoiceArticle

Comparative Reverse Vaccinology of Piscirickettsia salmonis, Aeromonas salmonicida, Yersinia ruckeri, Vibrio anguillarum and Moritella viscosa, Frequent Pathogens of Atlantic Salmon and Lumpfish Aquaculture

by Joy Chukwu-Osazuwa, Trung Cao, Ignacio Vasquez, Hajarooba Gnanagobal, Ahmed Hossain, Vimbai Irene Machimbirike and Javier Santander

Vaccines 2022, 10(3), 473; https://doi.org/10.3390/vaccines10030473 - 18 Mar 2022

Cited by 21 | Viewed by 5852

Abstract

Marine finfish aquaculture is affected by diverse infectious diseases, and they commonly occur as co-infection. Some of the most frequent and prevalent Gram-negative bacterial pathogens of the finfish aquaculture include Piscirickettsia salmonis, Aeromonas salmonicida, Yersinia ruckeri, Vibrio anguillarum and Moritella [...] Read more.

Marine finfish aquaculture is affected by diverse infectious diseases, and they commonly occur as co-infection. Some of the most frequent and prevalent Gram-negative bacterial pathogens of the finfish aquaculture include Piscirickettsia salmonis, Aeromonas salmonicida, Yersinia ruckeri, Vibrio anguillarum and Moritella viscosa. To prevent co-infections in aquaculture, polyvalent or universal vaccines would be ideal. Commercial polyvalent vaccines against some of these pathogens are based on whole inactivated microbes and their efficacy is controversial. Identification of common antigens can contribute to the development of effective universal or polyvalent vaccines. In this study, we identified common and unique antigens of P. salmonis, A. salmonicida, Y. ruckeri, V. anguillarum and M. viscosa based on a reverse vaccinology pipeline. We screened the proteome of several strains using complete available genomes and identified a total of 154 potential antigens, 74 of these identified antigens corresponded to secreted proteins, and 80 corresponded to exposed outer membrane proteins (OMPs). Further analysis revealed the outer membrane antigens TonB-dependent siderophore receptor, OMP assembly factor BamA, the LPS assembly protein LptD and secreted antigens flagellar hook assembly protein FlgD and flagellar basal body rod protein FlgG are present in all pathogens used in this study. Sequence and structural alignment of these antigens showed relatively low percentage sequence identity but good structural homology. Common domains harboring several B-cells and T-cell epitopes binding to major histocompatibility (MHC) class I and II were identified. Selected peptides were evaluated for docking with Atlantic salmon (Salmo salar) and Lumpfish MHC class II. Interaction of common peptide-MHC class II showed good in-silico binding affinities and dissociation constants between −10.3 to −6.5 kcal mol⁻¹ and 5.10 × 10⁻⁹ to 9.4 × 10⁻⁶ M. This study provided the first list of antigens that can be used for the development of polyvalent or universal vaccines against these Gram-negative bacterial pathogens affecting finfish aquaculture. Full article

(This article belongs to the Special Issue Vaccines for Aquaculture)

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14 pages, 331 KB

Open AccessEditor’s ChoiceReview

Utilization of Viral Vector Vaccines in Preparing for Future Pandemics

by Kimberly A. Hofmeyer, Katherine M. Bianchi and Daniel N. Wolfe

Vaccines 2022, 10(3), 436; https://doi.org/10.3390/vaccines10030436 - 12 Mar 2022

Cited by 14 | Viewed by 4972

Abstract

As the global response to COVID-19 continues, government stakeholders and private partners must keep an eye on the future for the next emerging viral threat with pandemic potential. Many of the virus families considered to be among these threats currently cause sporadic outbreaks [...] Read more.

As the global response to COVID-19 continues, government stakeholders and private partners must keep an eye on the future for the next emerging viral threat with pandemic potential. Many of the virus families considered to be among these threats currently cause sporadic outbreaks of unpredictable size and timing. This represents a major challenge in terms of both obtaining sufficient funding to develop vaccines, and the ability to evaluate clinical efficacy in the field. However, this also presents an opportunity in which vaccines, along with robust diagnostics and contact tracing, can be utilized to respond to outbreaks as they occur, and limit the potential for further spread of the disease in question. While mRNA-based vaccines have proven, during the COVID-19 response, to be an effective and safe solution in terms of providing a rapid response to vaccine development, virus vector-based vaccines represent a class of vaccines that can offer key advantages in certain performance characteristics with regard to viruses of pandemic potential. Here, we will discuss some of the key pros and cons of viral vector vaccines in the context of preparing for future pandemics. Full article

(This article belongs to the Special Issue A Modern Take on Replicating Viral Vaccines)

13 pages, 456 KB

Open AccessEditor’s ChoiceReview

Roles of the Tol/Pal System in Bacterial Pathogenesis and Its Application to Antibacterial Therapy

by Hidetada Hirakawa, Kazutomo Suzue and Haruyoshi Tomita

Vaccines 2022, 10(3), 422; https://doi.org/10.3390/vaccines10030422 - 10 Mar 2022

Cited by 15 | Viewed by 5949

Abstract

The Tol/Pal system (also written as “The Tol-Pal system”) is a set of protein complexes produced by most Gram-negative bacteria. It comprises the inner membrane-associated and the outer membrane-anchored subunits composed of the TolA, TolQ, and TolR proteins and the TolB and Pal [...] Read more.

The Tol/Pal system (also written as “The Tol-Pal system”) is a set of protein complexes produced by most Gram-negative bacteria. It comprises the inner membrane-associated and the outer membrane-anchored subunits composed of the TolA, TolQ, and TolR proteins and the TolB and Pal proteins, respectively. Although the Tol/Pal system was first defined as bacterial proteins involved in colicin uptake of Escherichia coli, its global roles have been characterized in several studies as mentioned in this article. Pathogenesis of many Gram-negative pathogens is sustained by the Tol/Pal system. It is also essential for cell growth and fitness in some pathogens. Therefore, the Tol/Pal system is proposed as a potential target for antimicrobial chemotherapy. Although the tol/pal mutants are low in virulence, they still have the ability to stimulate the immune system. The Pal protein is highly immunogenic and induces both adaptive and innate immune responses. Therefore, the tol/pal mutant strains and Pal proteins also have potential vaccine properties. For these reasons, the Tol/Pal system represents a promising research target in the development of antibacterial therapeutic strategies for refractory infections caused by multi-drug-resistant (MDR), Gram-negative pathogens. In this paper, we summarize studies on the Tol/Pal system associated with bacterial pathogenesis and vaccine development. Full article

(This article belongs to the Special Issue Development of Attenuated Vaccine)

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14 pages, 583 KB

Open AccessEditor’s ChoiceReview

Long-Term Effects of Human Papillomavirus Vaccination in Clinical Trials and Real-World Data: A Systematic Review

by Megumi Kurosawa, Masayuki Sekine, Manako Yamaguchi, Risa Kudo, Sharon J. B. Hanley, Megumi Hara, Sosuke Adachi, Yutaka Ueda, Etsuko Miyagi, Sayaka Ikeda, Asami Yagi and Takayuki Enomoto

Vaccines 2022, 10(2), 256; https://doi.org/10.3390/vaccines10020256 - 8 Feb 2022

Cited by 13 | Viewed by 9908

Abstract

The preventive effect of HPV vaccines against anogenital and oropharyngeal cancers has been proven in both clinical trials and real-world data. We reviewed the published evidence about the long-term efficacy and effectiveness of the HPV vaccine in available papers of clinical trials and [...] Read more.

The preventive effect of HPV vaccines against anogenital and oropharyngeal cancers has been proven in both clinical trials and real-world data. We reviewed the published evidence about the long-term efficacy and effectiveness of the HPV vaccine in available papers of clinical trials and real-world data. As far as we searched, the longest period of preventive effect for the bivalent, 4-valent, and 9-valent vaccine were 11 years in the Costa Rica trial, 14 years in the FUTURE II, and 8 years in the LTFU extension study of V503-002 and the Scandinavian study, respectively. The sustained clinical effect during the observation period was longest for the 4-valent vaccine. In real-world data, the longest observation period of the vaccine effectiveness was 12 years in an Australian study for the 4-valent vaccine. On the other hand, the longest period of long-term persistence of HPV vaccine-induced seropositivity was 14 years in FUTURE II for the 4-valent vaccine. For the bivalent vaccine, additional long-term follow-up studies may not have been planned due to the launch of the 4-valent and 9-valent vaccines. In some studies of the 9-valent vaccine, the results have not yet been published because of the short observation period. The additional results are expected in the future. In a national immunization program, most girls and boys are inoculated with HPV vaccine by the time puberty begins; thus, it is important to monitor the vaccine effect at least until the sexually active period in their 20s and 30s. Full article

(This article belongs to the Special Issue Epidemiological Studies of HPV Infection and Vaccination)

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13 pages, 275 KB

Open AccessEditor’s ChoiceArticle

Tipping the Fencesitters—The Impact of a Minimal Intervention Enhanced with Biological Facts on Swiss Student Teachers’ Perception of HPV Vaccination Safety

by Alla Keselman and Albert Zeyer

Vaccines 2022, 10(2), 175; https://doi.org/10.3390/vaccines10020175 - 23 Jan 2022

Cited by 8 | Viewed by 3618

Abstract

Not much is known about the role of scientific knowledge in vaccination decision making. This study is based on previous findings that the concern about the human papillomavirus (HPV) agent mutating back to a virulent HPV was common among Swiss student teachers and [...] Read more.

Not much is known about the role of scientific knowledge in vaccination decision making. This study is based on previous findings that the concern about the human papillomavirus (HPV) agent mutating back to a virulent HPV was common among Swiss student teachers and turned out to be one factor of vaccine hesitancy. The study investigate the impact of a standard public health brochure describing the effectiveness, safety, and importance of HPV vaccination on young student teachers, and the additional effect of supplementing the standard brochure with biological arguments against the mutation concerns. It uses a pre-posttest design and assigns participants randomly to two groups, one reviewing a standard public health brochure, the other the same brochure enhanced with additional biological information. Participants in both groups showed a significant positive change in their beliefs about vaccination safety, effectiveness, and importance in preventing cervical cancer. Post hoc analysis showed significant safety beliefs gain for the subgroup of participants who received the biology-enhanced text and held moderate, rather than high or low, pretest safety beliefs—the so-called fencesitters. We conclude that these fencesitters may particularly profit from even minimal (biologically supplemented) interventions, an effect that should receive more attention in future research. Full article

(This article belongs to the Special Issue Vaccine Hesitancy and Child Immunizations: Rationales, Issues and Knowledge Gaps 2.0)

10 pages, 1499 KB

Open AccessEditor’s ChoiceArticle

Reduced Titers of Circulating Anti-SARS-CoV-2 Antibodies and Risk of COVID-19 Infection in Healthcare Workers during the Nine Months after Immunization with the BNT162b2 mRNA Vaccine

by Luca Coppeta, Cristiana Ferrari, Giuseppina Somma, Andrea Mazza, Umberto D’Ancona, Fabbio Marcuccilli, Sandro Grelli, Marco Trabucco Aurilio, Antonio Pietroiusti, Andrea Magrini and Stefano Rizza

Vaccines 2022, 10(2), 141; https://doi.org/10.3390/vaccines10020141 - 18 Jan 2022

Cited by 37 | Viewed by 4128

Abstract

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has had a tremendous impact on health services; hundreds of thousands of healthcare workers (HCWs) have died from coronavirus disease 2019 (COVID-19). The introduction of the BNT162b2 mRNA vaccine in Italy provided recipients with [...] Read more.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has had a tremendous impact on health services; hundreds of thousands of healthcare workers (HCWs) have died from coronavirus disease 2019 (COVID-19). The introduction of the BNT162b2 mRNA vaccine in Italy provided recipients with significant protection against COVID-19 within one to two weeks after the administration of the second of the two recommended doses. While the vaccine induces a robust T cell response, the protective role of factors and pathways other than those related to memory B cell responses to specific SARS-CoV-2 antigens remains unclear. This retrospective study aimed to evaluate the determinants of serological protection in a group of vaccinated HCWs (n = 793) by evaluating circulating levels of antiviral spike receptor-binding domain (S-RBD) antibodies during the nine-month period following vaccination. We found that 99.5% of the HCWs who received the two doses of the BNT162b2 vaccine developed protective antibodies that were maintained at detectable levels for as long as 250 days after the second dose of the vaccine. Multivariate analysis was performed on anti-S-RBD titers in a subgroup of participants (n = 173) that were evaluated twice during this period. The results of this analysis reveal that the antibody titer observed at the second time point was significantly related to the magnitude of the primary response, the time that had elapsed between the first and the second evaluation, and a previous history of SARS-CoV-2 infection. Of importance is the finding that despite waning antibody titers following vaccination, none of the study participants contracted severe COVID-19 during the observational period. Full article

(This article belongs to the Special Issue Feature Papers of Epidemiology and Vaccines)

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9 pages, 209 KB

Open AccessEditor’s ChoiceReview

Covid-19-Associated Pulmonary Aspergillosis: The Other Side of the Coin

by Claudio Costantini, Frank L. van de Veerdonk and Luigina Romani

Vaccines 2020, 8(4), 713; https://doi.org/10.3390/vaccines8040713 - 1 Dec 2020

Cited by 29 | Viewed by 4780

Abstract

The immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a critical factor in the clinical presentation of COVID-19, which may range from asymptomatic to a fatal, multi-organ disease. A dysregulated immune response not only compromises the ability of the host [...] Read more.

The immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a critical factor in the clinical presentation of COVID-19, which may range from asymptomatic to a fatal, multi-organ disease. A dysregulated immune response not only compromises the ability of the host to resolve the viral infection, but may also predispose the individual to secondary bacterial and fungal infections, a risk to which the current therapeutic immunomodulatory approaches significantly contribute. Among the secondary infections that may occur in COVID-19 patients, coronavirus-associated pulmonary aspergillosis (CAPA) is emerging as a potential cause of morbidity and mortality, although many aspects of the disease still remain unresolved. With this opinion, we present the current view of CAPA and discuss how the same mechanisms that underlie the dysregulated immune response in COVID-19 increase susceptibility to Aspergillus infection. Likewise, resorting to endogenous pathways of immunomodulation may not only restore immune homeostasis in COVID-19 patients, but also reduce the risk for aspergillosis. Therefore, CAPA represents the other side of the coin in COVID-19 and our advances in the understanding and treatment of the immune response in COVID-19 should represent the framework for the study of CAPA. Full article

(This article belongs to the Special Issue Our Immune System Is the First Line of Defense towards Infections: Modulation of the Immune System to Boost the Host Defense Response towards Pathogens)

14 pages, 1756 KB

Open AccessEditor’s ChoiceArticle

Influences on Attitudes Regarding Potential COVID-19 Vaccination in the United States

by Kendall Pogue, Jamie L. Jensen, Carter K. Stancil, Daniel G. Ferguson, Savannah J. Hughes, Emily J. Mello, Ryan Burgess, Bradford K. Berges, Abraham Quaye and Brian D. Poole

Vaccines 2020, 8(4), 582; https://doi.org/10.3390/vaccines8040582 - 3 Oct 2020

Cited by 385 | Viewed by 31367

Abstract

The COVID-19 pandemic continues to ravage the world, with the United States being highly affected. A vaccine provides the best hope for a permanent solution to controlling the pandemic. However, to be effective, a vaccine must be accepted and used by a large [...] Read more.

The COVID-19 pandemic continues to ravage the world, with the United States being highly affected. A vaccine provides the best hope for a permanent solution to controlling the pandemic. However, to be effective, a vaccine must be accepted and used by a large majority of the population. The aim of this study was to understand the attitudes towards and obstacles facing vaccination with a potential COVID-19 vaccine. To measure these attitudes a survey was administered to 316 respondents across the United States by a survey corporation. Structural equation modeling was used to analyze the relationships of several factors with attitudes toward potential COVID-19 vaccination. Prior vaccine usage and attitudes predicted attitudes towards COVID-19 vaccination. Assessment of the severity of COVID-19 for the United States was also predictive. Approximately 68% of all respondents were supportive of being vaccinated for COVID-19, but side effects, efficacy and length of testing remained concerns. Longer testing, increased efficacy and development in the United States were significantly associated with increased vaccine acceptance. Messages promoting COVID-19 vaccination should seek to alleviate the concerns of those who are already vaccine-hesitant. Messaging directed at the benefits of vaccination for the United States as a country would address the second predictive factor. Enough time should be taken to allay concerns about both short- and long-term side effects before a vaccine is released. Full article

(This article belongs to the Special Issue Vaccination and Public Health: Optimizing Vaccine Uptake through the Application of Social and Behavioral Science Theory, Principles, and Strategies)

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11 pages, 523 KB

Open AccessEditor’s ChoiceArticle

Relationship between Citizens’ Health Engagement and Intention to Take the COVID-19 Vaccine in Italy: A Mediation Analysis

by Guendalina Graffigna, Lorenzo Palamenghi, Stefania Boccia and Serena Barello

Vaccines 2020, 8(4), 576; https://doi.org/10.3390/vaccines8040576 - 1 Oct 2020

Cited by 141 | Viewed by 10769

Abstract

The actual effectiveness of the still-to-come vaccination against the coronavirus SARS-CoV-2 might be challenged by vaccine hesitancy, a rather common and known phenomenon whose psychological predictors are, nevertheless, still largely debated. Our study aims at understanding how adult citizens’ health engagement, perceived COVID-19 [...] Read more.

The actual effectiveness of the still-to-come vaccination against the coronavirus SARS-CoV-2 might be challenged by vaccine hesitancy, a rather common and known phenomenon whose psychological predictors are, nevertheless, still largely debated. Our study aims at understanding how adult citizens’ health engagement, perceived COVID-19 susceptibility and severity, and general vaccine-related attitudes affect the willingness to vaccinate against COVID-19. To that end, on a sample of Italian citizens, we implemented a path model to test the impact of health engagement on the willingness to vaccinate against SARS-CoV-2, and whether this relationship is direct or mediated by the general attitude towards vaccines and the risk perception. Moreover, we tested the configural and weak invariance of the model across gender and three age groups. Results show that health engagement is positively related to the intention to vaccinate and that this relationship is partially mediated by the general attitude towards vaccines. The model appears invariant across genders and partially invariant across age groups, showing some differences in the role of perceived susceptibility. These findings vouch for the implementation of educational campaigns aimed at sustaining future vaccination programs that also include health engagement promotion. Full article

(This article belongs to the Special Issue Vaccine Hesitancy and Child Immunizations: Rationales, Issues and Knowledge Gaps)

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