Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (215)

Search Parameters:
Keywords = influenza vaccine uptake

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
13 pages, 209 KiB  
Article
Seasonal Influenza Vaccination Uptake Among Australian Healthcare Professionals: An Archetype for Success
by Caroline M. Hall, Anthony Cotton, Adrian Webster, Mary Bushell and Holly L. Northam
Vaccines 2025, 13(1), 71; https://doi.org/10.3390/vaccines13010071 - 14 Jan 2025
Viewed by 468
Abstract
Background/Objectives: Qualitative research suggests there may be identifiable characteristics that form a health professional (HCP) archetype associated with habitual seasonal influenza vaccination (SIV). However, the validity of this archetype requires further investigation, ideally within a theoretical framework that can elucidate this association and [...] Read more.
Background/Objectives: Qualitative research suggests there may be identifiable characteristics that form a health professional (HCP) archetype associated with habitual seasonal influenza vaccination (SIV). However, the validity of this archetype requires further investigation, ideally within a theoretical framework that can elucidate this association and its generalisability to other vaccines. This study aims to confirm key HCP archetype characteristics associated with SIV, as informed by prior qualitative research findings, and test the generalisability of the association between this archetype and SIV to COVID-19 vaccine acceptance. Method: A cross-sectional survey was designed and distributed to an Australian HCP sample consisting of practicing nurses, midwives, pharmacists, and medical practitioners. The anonymous online survey measured key characteristics that predict vaccination behaviour and intention. Results: Most participants (n = 173) demonstrated habitual SIV behaviour (77.91%) associated with the intention to vaccinate in the future. Survey findings supported the HCP archetype, as key constructs were associated with vaccination intention and behaviour, including heightened professional responsibility, vaccine confidence, and protection of self and patients. Furthermore, results suggested progressing vaccination intention to behaviour, overcoming vaccine complacency, is possible through the provision of free, accessible vaccination services. These critical factors were broadly generalisable to the COVID-19 vaccine. Conclusions: A vaccination-positive HCP archetype, supported by access to free, convenient vaccination services, was associated with the likelihood of future vaccination behaviour, including in future pandemic response scenarios. However, it will be important to ensure that HCP vaccine knowledge gaps are minimised to enhance trust in this cohort to enable broad success. Full article
14 pages, 2653 KiB  
Article
Physicians’ Intentions to Recommend Influenza Vaccine: A Multi-Centered Hospital-Based Study Using the Theory of Planned Behavior in Bangladesh
by Md Abdullah Al Jubayer Biswas, Mahbubur Rahman, Sazzad Hossain Khan, Ahamed Khairul Basher, Md Ariful Islam, Ashrak Shad Pyash, Homayra Rahman Shoshi, Md Altaf Ahmed Riaj, Md Nazrul Islam, Md Arif Rabbany, Md Azizul Haque, Shishir Ranjan Chakraborty, Syeda Rukhshana Parvin, Mahmudur Rahman, Fahmida Chowdhury, Tahmina Shirin and Md. Zakiul Hassan
Int. J. Environ. Res. Public Health 2025, 22(1), 84; https://doi.org/10.3390/ijerph22010084 - 9 Jan 2025
Viewed by 541
Abstract
Background: Influenza remains a significant public health challenge in low- and middle-income countries (LMICs) like Bangladesh, where vaccine uptake remains low despite the substantial disease burden. Physicians play a vital role in promoting vaccination, yet their intentions and influencing factors are not well [...] Read more.
Background: Influenza remains a significant public health challenge in low- and middle-income countries (LMICs) like Bangladesh, where vaccine uptake remains low despite the substantial disease burden. Physicians play a vital role in promoting vaccination, yet their intentions and influencing factors are not well understood. Methods: We conducted a cross-sectional study from June to October 2022 across four tertiary-level hospitals in Bangladesh using a questionnaire grounded in the Theory of Planned Behavior (TPB). Hierarchical logistic regression was employed to identify factors associated with vaccine recommendation intentions. Results: Among 972 physicians with an average age of 32.1 years, 40.1% intended to recommend and administer the influenza vaccine. Most (85.3%) agreed vaccination reduces risk, 65.5% desired vaccination for self-protection, 63.5% would vaccinate if available at work, and 85.3% anticipated Ministry of Health support. Male (OR = 1.9, 95% CI: 1.5–2.3) and married (OR = 1.5, 95% CI: 1.1–1.9) physicians were more likely to recommend vaccination. Each unit increase in attitude score doubled the likelihood of recommending the vaccine (OR = 2.0, 95% CI: 1.4–3.0). Conclusions: Physicians’ influenza vaccine recommendations in Bangladesh are suboptimal, influenced by gender, marital status, and attitudes. Targeted educational interventions addressing attitudinal barriers and leveraging institutional support could improve recommendation practices. Full article
Show Figures

Figure 1

14 pages, 537 KiB  
Article
Characteristics of the First Italian Older Adults Vaccinated with an Adjuvanted Respiratory Syncytial Virus (RSV) Vaccine
by Alexander Domnich, Andrea Orsi, Piero Luigi Lai, Elvira Massaro, Carlo-Simone Trombetta, Julieta Pastorino, Charlott Roihl, Marianna Pianta, Giancarlo Icardi and Donatella Panatto
Medicina 2025, 61(1), 67; https://doi.org/10.3390/medicina61010067 - 3 Jan 2025
Viewed by 578
Abstract
Background and Objectives: Three respiratory syncytial virus (RSV) vaccines have been recently made available for older adults. Understanding the principal characteristics of the first vaccine-takers can pave the way for a successful vaccination campaign. The objective of this study was to explore [...] Read more.
Background and Objectives: Three respiratory syncytial virus (RSV) vaccines have been recently made available for older adults. Understanding the principal characteristics of the first vaccine-takers can pave the way for a successful vaccination campaign. The objective of this study was to explore the sociodemographic and clinical characteristics of the first Italian users of an adjuvanted RSV vaccine and their attitudes towards RSV and vaccination. Materials and Methods: This cross-sectional study was conducted in 2024 in Liguria (Italy). Individuals aged ≥60 years with no contraindications to the adjuvanted vaccine RSVPreF3 OA were eligible. Following vaccination, subjects filled in a questionnaire, which comprised items on sociodemographic and clinical characteristics, attitudes towards RSV and RSV vaccination and a vaccination trust indicator (VTI). Results: A total of 453 vaccinees completed the survey. Their mean age was 74.9 ± 8.0 years, and 50.6% were males. Nine of ten (89.2%) individuals had ≥1 co-morbidity, of which cardiovascular conditions (70.4%), respiratory diseases (27.6%) and diabetes (18.5%) were the most common. Uptake of the routine vaccines was high: 91.2% and 98.7% received the 2023/2024 season influenza and ≥2 COVID-19 vaccines, respectively. The most common reasons for the current RSV vaccination were general practitioner advice (43.9%), followed by the willingness to be protected against (20.8%) and feelings of being at risk (16.6%) of RSV. The average VTI score was 91.5%, suggesting high trust in vaccines. More positive attitudes towards RSV vaccination were observed (p < 0.01) among subjects who received more COVID-19 vaccine doses, whose reasons for the current RSV vaccination were the willingness to be protected or to be in good health and the feeling of being at risk for RSV. Conclusions: The first Italian users of the novel RSVPreF3 OA vaccine were represented by high-risk individuals with a comparatively high prevalence of co-morbidities, high uptake of the seasonal respiratory vaccines and high trust in immunization. Full article
(This article belongs to the Section Epidemiology & Public Health)
Show Figures

Figure 1

12 pages, 394 KiB  
Article
The Epidemiology and Health Burdens of Influenza Infections Amongst Hospitalized Children Under 5 Years of Age in Jordan: A National Multi-Center Cross-Sectional Study
by Munir Abu-Helalah, Samah F. Al-Shatnawi, Mohammad Abu Lubad, Enas Al-Zayadneh, Mohammad Al-Hanaktah, Mea’ad Harahsheh, Montaha AL-Iede, Omar Nafi, Ruba Yousef, Ihsan Almaaitah, Mai Ababneh, Toqa AlZubi, Rand Abu Mahfouz, Heba Adaylah, Hamzeh AlHajaj, Mohammad Al Tamimi and Simon B. Drysdale
Vaccines 2025, 13(1), 12; https://doi.org/10.3390/vaccines13010012 - 26 Dec 2024
Viewed by 622
Abstract
Background/Objectives: Seasonal influenza is a significant global health concern, causing substantial morbidity and mortality, particularly among high-risk groups such as children under five years old. There is scarce local evidence from developing countries such as Jordan on the burden of influenza, which has [...] Read more.
Background/Objectives: Seasonal influenza is a significant global health concern, causing substantial morbidity and mortality, particularly among high-risk groups such as children under five years old. There is scarce local evidence from developing countries such as Jordan on the burden of influenza, which has limited preventive measures. This multi-center national cross-sectional study aimed to assess the epidemiological and clinical burden of influenza among hospitalized children under five years old in Jordan. Methods: Data were collected from 1000 participants across four hospitals between November 2022 and April 2023. Nasopharyngeal specimens were analyzed using multiplex RT-PCR to determine positivity for influenza A and B. Results: We found a 9.9% positivity rate, predominantly influenza A (8.4%), while influenza B was positive among 1.5% of the participants. Positivity rates were higher in older age groups, particularly children older than 2 years. Influenza-positive cases exhibited longer fever durations and higher rates of sore throat. There were no positive influenza cases among participants if they or any of their family members received the influenza vaccine, highlighting the vaccine’s protective role. Logistic regression analysis identified maternal smoking during pregnancy as a significant predictor of influenza positivity. Conclusions: The findings of this study underscore the need for enhanced vaccination efforts and public health policies targeting young children and pregnant women in Jordan. Expanding vaccination uptake could significantly mitigate the burden of influenza and its complications in this vulnerable population. Full article
(This article belongs to the Special Issue Vaccination, Public Health and Epidemiology)
Show Figures

Figure 1

23 pages, 1261 KiB  
Systematic Review
Effectiveness of General Practitioners’ Involvement in Adult Vaccination Practices: A Systematic Review and Meta-Analysis of International Evidence
by Andrea Ceccarelli, Gabriele Munafò, Francesco Sintoni, Christian Cintori, Davide Gori and Marco Montalti
Vaccines 2024, 12(12), 1438; https://doi.org/10.3390/vaccines12121438 - 20 Dec 2024
Viewed by 578
Abstract
Background: General practitioners (GPs) and primary care units collaborate with Prevention Departments (PDs) to improve immunization by participating in vaccination campaigns, sharing tools, and implementing educational programs to raise patient awareness. This review aimed to identify effective strategies for involving GPs in PD [...] Read more.
Background: General practitioners (GPs) and primary care units collaborate with Prevention Departments (PDs) to improve immunization by participating in vaccination campaigns, sharing tools, and implementing educational programs to raise patient awareness. This review aimed to identify effective strategies for involving GPs in PD vaccination practices. Methods: A systematic review following PRISMA guidelines was conducted on MEDLINE, TripDatabase, ClinicalTrials, CINAHL, and Cochrane up to January 2024 to identify full-text studies in English evaluating the effectiveness of GP involvement. A meta-analysis was also performed. Results: Of 1018 records, 15 studies were included, with an intermediate quality assessment. Studies originated from the United States (n = 9), Europe (5), Singapore (1), and China (1). Eight studies investigated educational programs for GPs, while seven focused on organizational or technological interventions to enhance immunization practices. Twelve studies reported increased vaccine uptake after intervention. Vaccines addressed included influenza, SARS-CoV-2, pneumococcal, zoster, and trivalent (diphtheria, tetanus, pertussis). Interventions involving GPs in PD vaccination campaigns, focusing on organizational or technological strategies, demonstrated a significant increase in vaccine uptake (OR = 1.15; 95% CI: 1.03–1.27; p < 0.0001; I2 = 96%). Conclusions: GPs emerged as valuable allies for PDs due to their extensive territorial reach and trusted relationships with patients. Additionally, up-to-date organizational and technological tools could play a decisive role in increasing vaccine uptakes. This study, offering valuable insights into the effectiveness of GPs involvement, may be useful to implement similar intervention in different contexts. Full article
Show Figures

Figure 1

16 pages, 722 KiB  
Review
Seasonal Influenza Vaccination Programs in the Americas: A Platform for Sustainable Life-Course Immunization and Its Role for Pandemic Preparedness and Response
by Francisco Nogareda, Margherita Ghiselli, Martha Velandia-González, Bremen de Mucio, Jorge Jara, Paula Couto, Angel Rodriguez, Marc Rondy, Andrea Vicari, Murat Hakan Ozturk, Shoshanna Goldin, Alba Vilajeliu, Eva Leidman, Jaymin Patel, Julie Carlton, Ashley L. Fowlkes, Eduardo Azziz-Baumgartner, Daniel Salas Peraza and Alba Maria Ropero
Vaccines 2024, 12(12), 1415; https://doi.org/10.3390/vaccines12121415 - 16 Dec 2024
Viewed by 925
Abstract
Background: Vaccination is one of the most effective measures to prevent influenza illness and its complications. Since the 1980s, countries and territories in the Americas have progressively implemented influenza vaccination operations in high-risk priority groups—such as older adults, pregnant persons, persons with comorbidities [...] Read more.
Background: Vaccination is one of the most effective measures to prevent influenza illness and its complications. Since the 1980s, countries and territories in the Americas have progressively implemented influenza vaccination operations in high-risk priority groups—such as older adults, pregnant persons, persons with comorbidities and health workers. Methods: In this review, we present the history and progress of the seasonal influenza program in the Americas, how the program contributed to the efficient and timely roll-out of the COVID-19 vaccines during the pandemic, and how the program can be used to promote immunization operations across the life span for existing and future vaccines. Results: The influenza A(H1N1)pdm09 pandemic in 2009 and the COVID-19 pandemic in 2020–2023 underscored the importance of having a robust seasonal influenza vaccination program for pandemic preparedness and response. Overall, countries with existing seasonal influenza vaccination programs were better prepared and rolled out the delivery of COVID-19 vaccines more quickly and effectively compared to other countries where the influenza vaccination platform was weak or non-existent. Conclusions: Traditionally, national immunization programs of developing countries have been predominately focused on newborns, children younger than five years and school-aged children while often limiting their investment in effective adult vaccination programs; these programs are typically isolated to high-income countries. Countries in Latin America have been the exception, with strong influenza vaccination programs for adults regardless of national income level. The presence of functional and effective adult influenza vaccination programs can also facilitate the acceptance and uptake of other adult vaccines targeting priority groups at higher risk for severe illness or complications. Full article
(This article belongs to the Special Issue 50 Years of Immunization—Steps Forward)
Show Figures

Figure 1

12 pages, 230 KiB  
Article
COVID-19 Vaccine Hesitancy Among Pediatric Oncology and Bone Marrow Transplant Patients
by Sarah A. O’Neill, Son Tran, Cora Constantinescu and Tony H. Truong
Vaccines 2024, 12(12), 1407; https://doi.org/10.3390/vaccines12121407 - 13 Dec 2024
Viewed by 762
Abstract
Background/Objectives: Vaccine hesitancy among immunocompromised patients is complex and not well understood. This study aimed to determine the rate of COVID-19 vaccine hesitancy among pediatric oncology and bone marrow transplant (BMT) patients and to understand associated factors. Methods: Parents of patients (≤18 [...] Read more.
Background/Objectives: Vaccine hesitancy among immunocompromised patients is complex and not well understood. This study aimed to determine the rate of COVID-19 vaccine hesitancy among pediatric oncology and bone marrow transplant (BMT) patients and to understand associated factors. Methods: Parents of patients (≤18 years) with cancer or post-BMT completed the Parent Attitudes about Childhood Vaccines Survey. A COVID-19 vaccine hesitancy score (VHS-COVID) was calculated from 0 to 100 (higher scores indicating increasing hesitancy). A small group of patients (patients older than 15 years) were also surveyed directly. Results: Among 113 parent respondents, the majority were female (58%) and at least college/university educated (78%). The majority (73%) of patients had cancer (61% leukemia/lymphoma, 37% solid/CNS tumors), while 27% had received BMT for malignant and non-malignant conditions. Only 48% of patients had been vaccinated against COVID-19, compared to 88% of parents. Ineligibility due to phase of cancer/BMT treatment (27%), vaccine hesitancy (24%), and age (24%) were the top three reasons for not vaccinating against COVID-19. Only 13% of parents said they would “definitely vaccinate” if their child became eligible. VHS-COVID scores were higher for parents of patients in surveillance versus active therapy (mean 61 vs. 48; p = 0.03). Parents who had received fewer COVID-19 vaccine doses (0–1 vs. ≥2) were more hesitant toward all vaccines (p = 0.0002), COVID-19 vaccines (p = 0.0003), and influenza vaccines (p = 0.005). Conclusions: Vaccine hesitancy is common among this population and was demonstrated through beliefs (hesitancy scores) as well as vaccine uptake. Future work should focus on education targeting vaccine eligibility and engaging with vaccine hesitant families in the immunocompromised community. Full article
(This article belongs to the Special Issue 50 Years of Immunization—Steps Forward)
21 pages, 1232 KiB  
Article
Vaccine Acceptance Among Pregnant Women in Israel During COVID-19: Influences and Decision-Making Factors
by Noa Feldman, Michal Bitan, Maya Alayev and Orna Tal
Vaccines 2024, 12(12), 1404; https://doi.org/10.3390/vaccines12121404 - 12 Dec 2024
Viewed by 645
Abstract
Background and Objectives: In response to the COVID-19 pandemic, Israel prioritized pregnant women for vaccination, recognizing them as a high-risk group. This study aims to explore factors influencing the acceptance of Influenza, Pertussis (T-dap), and COVID-19 vaccines among pregnant women, focusing on attitudes, [...] Read more.
Background and Objectives: In response to the COVID-19 pandemic, Israel prioritized pregnant women for vaccination, recognizing them as a high-risk group. This study aims to explore factors influencing the acceptance of Influenza, Pertussis (T-dap), and COVID-19 vaccines among pregnant women, focusing on attitudes, social norms, perceived control, and risk perceptions. Additionally, the study compares acceptance patterns between traditional vaccines and the newer COVID-19 vaccine. Methods: A prospective cohort study was conducted between December 2019 and December 2021 involving 449 predominantly Israeli pregnant women. A survey was administered to gather data on demographics, obstetric history, vaccination history, and factors influencing vaccination decisions. Results: COVID-19 vaccine uptake was the highest at 64% (202/314), followed by T-dap at 49% (221/449) and Influenza at 32% (146/449). Multivariable logistic regression showed that non-religious women and those with academic education were more likely to accept vaccines, especially the COVID-19 vaccine. Physician recommendations were the most influential factor in vaccine acceptance, while internet and media sources played a significant role in shaping COVID-19 vaccine decisions. Perceived risks varied: Whooping Cough was seen as the greatest threat to newborns, while COVID-19 posed the highest risk to mothers. Analyzing maternal and neonatal disease perception using multivariable linear regression, we found that information on maternal and neonatal Flu, Whooping Cough, and COVID-19 was significantly positively correlated with disease perception for each condition. Conclusions: Healthcare providers play a crucial role in influencing vaccine decisions, especially through personalized communication. Strategies targeting religious communities and leveraging media can help address vaccine hesitancy, ultimately improving maternal and neonatal health outcomes. Full article
(This article belongs to the Section Human Vaccines and Public Health)
Show Figures

Figure 1

10 pages, 228 KiB  
Article
Vaccination Coverage for Medically Indicated Vaccines in a Convenience Sample of Severely Immunocompromised Patients with COVID-19: An Observational Cohort Study
by Elsemieke te Linde, Marjolein P. M. Hensgens, Albert M. Vollaard, Annelies Verbon and Anke H. W. Bruns
Vaccines 2024, 12(12), 1383; https://doi.org/10.3390/vaccines12121383 - 9 Dec 2024
Viewed by 849
Abstract
Background: In recent decades, the number of immunocompromised patients (ICPs) has increased significantly. ICPs have an impaired immune system, making them susceptible to complicated infections. To protect them from infections, ICPs are eligible to receive several medically indicated vaccines. To obtain insight into [...] Read more.
Background: In recent decades, the number of immunocompromised patients (ICPs) has increased significantly. ICPs have an impaired immune system, making them susceptible to complicated infections. To protect them from infections, ICPs are eligible to receive several medically indicated vaccines. To obtain insight into the uptake of these medically indicated vaccines, we determined the coverage of these vaccines in ICPs. Methods: This observational cohort study was conducted at the University Medical Centre Utrecht, the Netherlands, from September 2021 to April 2022. All adult ICPs admitted for COVID-19 were asked to complete a questionnaire on their vaccination history (pneumococcal, herpes zoster, human papillomavirus vaccination, influenza, and COVID-19 vaccines) and history of vaccine-preventable infections. In addition, patients’ vaccination history was reviewed in medical files. Results: A total of 115 patients completed the questionnaire and were included. Although all patients had an indication for pneumococcal vaccination, only 22 received it (19%). Coverage for herpes zoster was low (1%, 1/106 eligible patients). Coverage for human papillomavirus vaccination (HPV) was also low (40%, two out of five eligible patients). In contrast, 92% of patients received vaccination against SARS-CoV-2, and 77% of patients received seasonal influenza vaccination. Conclusions: Although coverage for influenza and COVID-19 vaccination was high in ICPs, coverage for other medically indicated vaccines was low. Identifying which factors contributed to high COVID-19 and influenza vaccine uptake can help to improve vaccination rates for the other recommended vaccines. Clear guidelines for clinicians and the removal of organizational obstacles are needed to improve vaccination coverage. Full article
12 pages, 881 KiB  
Protocol
Promoting Influenza Vaccination Uptake Among Chinese Older Adults Based on Information–Motivation–Behavioral Skills Model and Conditional Economic Incentive: Protocol for Randomized Controlled Trial
by Hao Lin, Jiannan Xu, Refukaitijiang Abuduwayiti, Ying Ji, Yuhui Shi, Lanchao Zhang, Zhengli Shi, Mojun Ni, Sihong Tao, Bohao Yang, Shuhan Liu, Omar Galárraga, Chun Chang, Wangnan Cao and Phoenix Kit-Han Mo
Healthcare 2024, 12(23), 2361; https://doi.org/10.3390/healthcare12232361 - 25 Nov 2024
Viewed by 603
Abstract
Background: Influenza poses a substantial health burden, especially among older adults in China. While vaccination is one of the most effective preventions, influenza vaccine uptake rates among Chinese older adults remain low. This study examines the individual and combined effects of behavioral [...] Read more.
Background: Influenza poses a substantial health burden, especially among older adults in China. While vaccination is one of the most effective preventions, influenza vaccine uptake rates among Chinese older adults remain low. This study examines the individual and combined effects of behavioral interventions based on the Information–Motivation–Behavioral Skills (IMB) model and economic incentives in promoting influenza vaccine uptake among older adults living in China. Methods: The study will recruit 640 older adults living in eight communities that have not been covered by the free influenza vaccination policy. These eight communities (as clusters), stratified by urban and rural, will be randomized to four parallel arms, including a usual care arm, an IMB-based behavioral intervention arm, a conditional economic incentive arm, and a combined behavioral-economic arm. The interventions will start from the beginning of the flu season and last for about one month. Specifically, the IMB-based behavioral intervention encompasses health education brochures, healthcare provider-led lectures, interactive quizzes, and personalized consultations. The exact number of economic incentives is conditional on the timing of vaccination (a higher amount for early immunization) and the number of people within a household to be vaccinated at the same appointment (a higher amount for more people). The primary outcome is the influenza vaccination rate. Data will be gathered through vaccination records and questionnaires covering IMB-based vaccination cognitions. Mixed-effects models will be used to analyze the outcome of vaccination rate, reporting difference-in-differences estimates with 95% confidence intervals. Conclusions: The results of this study have the potential to inform influenza vaccination program scaleup among older adults who are not yet covered by the free influenza vaccination policy. Ethics and dissemination: Ethics approval has been granted by the ethics commission of Peking University Health Science Centre (IRB00001052-24090). Participants will be required to sign a written consent form. Findings will be reported in conferences and peer-reviewed publications in accordance with the recommendations of the Consolidated Standards of Reporting Trials. Registration number: This study was registered at the Chinese Clinical Trial Registry (ChiCTR2400090229). Full article
Show Figures

Figure 1

11 pages, 1327 KiB  
Article
Antigenic Divergence from the Seasonal Vaccine of the Influenza Virus Strains Circulating in Romania During Three Successive Seasons (2021–2024)
by Ovidiu Vlaicu, Leontina Banica, Robert Hohan, Marius Surleac, Dragoş Florea, Victor Daniel Miron, Andreea Tudor, Oana Săndulescu, Anca Cristina Drăgănescu, Dan Oțelea and Simona Paraschiv
Microorganisms 2024, 12(11), 2363; https://doi.org/10.3390/microorganisms12112363 - 19 Nov 2024
Viewed by 800
Abstract
Influenza viruses continue to be an important public health threat. Vaccination is the most effective measure to control the influenza virus circulation. However, these viruses are continuously evolving through antigenic drift/shift, and thus the vaccine efficiency is affected. The aim of this study [...] Read more.
Influenza viruses continue to be an important public health threat. Vaccination is the most effective measure to control the influenza virus circulation. However, these viruses are continuously evolving through antigenic drift/shift, and thus the vaccine efficiency is affected. The aim of this study was to characterize the viral strains circulating in Romania, in a population with declining vaccination coverage, during the last three cold seasons by evaluating the hemagglutinin antigenic relatedness to the vaccine strains. All the available sequences collected between August 2021 and June 2024 were analyzed by using phylogenetic analysis and the Pepitope model to predict vaccine efficacy. The results showed that the 2021/2022 influenza season was dominated by the circulation of highly diverse clades of A(H3N2) viruses with high mutational divergence as compared to the vaccine strain, which might contribute to the reduction in vaccine efficacy. During the 2022/2023 influenza season, both influenza A and B viruses were reported, with few antigenic site mutations. The 2023/2024 influenza season was dominated by the circulation of influenza A viruses: A/H1N1pdm09 clade 6B.1A.5a.2a and A/H3N2 clade 2a.3a.1. The clade 2a.3a.1 also showed high variability when compared to the vaccine strain, presumably leading to reduced vaccine efficacy. This study illustrates the high diversity of influenza viruses circulating in a population with low vaccination coverage during the previous cold seasons. The viral diversity impacted vaccine efficacy, hence the need for public health programs to increase vaccine uptake and improve vaccine formulation in order to limit viral transmission. Full article
Show Figures

Figure 1

15 pages, 1191 KiB  
Article
Protective Impact of Influenza Vaccination on Healthcare Workers
by Yimei Tian, Yue Ma, Jianchao Ran, Lifang Yuan, Xianhu Zeng, Lu Tan, Li Chen, Yifan Xu, Shaxi Li, Ting Huang and Hongzhou Lu
Vaccines 2024, 12(11), 1237; https://doi.org/10.3390/vaccines12111237 - 30 Oct 2024
Viewed by 1143
Abstract
Background: Influenza vaccine uptake among healthcare workers is crucial for preventing influenza infections, yet its effectiveness needs further investigation. Objectives: This prospective observational study aimed to assess the protective effect of influenza vaccination among healthcare workers in Shenzhen. Methods: We enrolled 100 participants, [...] Read more.
Background: Influenza vaccine uptake among healthcare workers is crucial for preventing influenza infections, yet its effectiveness needs further investigation. Objectives: This prospective observational study aimed to assess the protective effect of influenza vaccination among healthcare workers in Shenzhen. Methods: We enrolled 100 participants, with 50 receiving the 2023–2024 quadrivalent influenza vaccine (QIV) and 50 serving as unvaccinated controls. Epidemiological data were collected when the participants presented influenza-like illness. Serum samples were collected at three time points (pre-vaccination and 28 and 180 days after vaccination). Hemagglutination inhibition (HI) assay was performed against the strains included in the 2023–2024 QIV (H1N1, H3N2, BV and BY strains) to assess antibody protection levels. Demographics comparisons revealed no significant differences between the vaccinated and control groups (p > 0.05), ensuring group comparability. Results: The incidence of influenza-like illness was significantly lower in the vaccinated (18%) compared to the control group (36%; p = 0.046; OR = 0.39; 95% CI: 0.15 to 0.98). The vaccinated group also exhibited a higher rate of consecutive two-year vaccinations (48% vs. 24% in the control group, p < 0.05). Additionally, the vaccinated healthcare workers were more inclined to recommend vaccination to their families (80% vs. 48%, p < 0.05). HI titers against H1N1 (p < 0.01), H3N2 (p < 0.01), BV (p < 0.001) and BY (p < 0.01) significantly increased in the vaccinated group at 28 days post-vaccination. Moreover, a marked and sustained increase in HI titers against the H3N2 strain (p < 0.001) was observed at 180 days post-vaccination, highlighting the vaccine’s enduring impact on the immune response. The fold change in the HI titers, indicative of the magnitude of the immune response, was significantly higher for H1N1 (p < 0.01), H3N2 (p < 0.001), BV (p < 0.01) and BY (p < 0.05) among the vaccinated individuals compared to the control group, underscoring the vaccine’s efficacy in eliciting a robust and sustained antibody response. Conclusion: Influenza vaccination significantly reduces the incidence of influenza-like illness among healthcare workers and promotes a sustained immune response. The study supports the importance of annual vaccination for this group to enhance personal and public health. Full article
(This article belongs to the Special Issue Human Immune Responses to Infection and Vaccination)
Show Figures

Figure 1

13 pages, 643 KiB  
Article
Immune Response Against Influenza in a Cohort of Repeatedly Vaccinated Adults During the 2017/2018 and 2018/2019 Seasons
by Raquel Guiomar, Susana Pereira da Silva, Ana Paula Rodrigues, Inês Costa, Patrícia Conde, Paula Cristóvão, Pedro Pechirra, Paulo Estragadinho, Kamal Mansinho, Olav Hungnes, António Silva Graça and Baltazar Nunes
Vaccines 2024, 12(11), 1218; https://doi.org/10.3390/vaccines12111218 - 26 Oct 2024
Viewed by 847
Abstract
Background/Objectives: The influenza vaccination of healthcare workers (HCWs) is recommended each autumn and winter season by the relevant authorities in EU/EEA countries. The objective of this study was to evaluate the impact of repeated trivalent influenza vaccine (TIV) uptake during the 2017/2018 and [...] Read more.
Background/Objectives: The influenza vaccination of healthcare workers (HCWs) is recommended each autumn and winter season by the relevant authorities in EU/EEA countries. The objective of this study was to evaluate the impact of repeated trivalent influenza vaccine (TIV) uptake during the 2017/2018 and 2018/2019 seasons on vaccine-derived immunity against influenza. Methods: A cohort study of HCWs vaccinated with an annual TIV was conducted from October 2017 to June 2019. The protective antibodies against the influenza vaccine strains were assessed at three time points: prior to vaccination and at one and six months following vaccination for each season. Sera were tested by hemagglutination inhibition assay. Participants were grouped according to their history of TIV vaccination over four seasons (since 2015/16), with the groups designated as “frequently vaccinated” (≥3 vaccines) and “occasionally vaccinated” (≤2 vaccines). Seroprevalence, geometric mean titer (GMT) and seroconversion rate were compared between the frequently and occasionally vaccinated groups. Results: A total of 97 healthcare workers (HCWs) were enrolled in the study; 49 HCWs participated in both seasons. Thirty-two (43.2%) and forty-three (59.7%) individuals had ≥3 vaccines since 2015/2016, at recruitment and during the 2017/2018 and 2018/2019 influenza seasons, respectively. One month following vaccination, HCWs who had received occasional vaccinations demonstrated a higher prevalence of protective antibodies and a greater GMT for both influenza A(H1N1)pdm09 and A(H3N2) viruses. For influenza B Victoria, the frequently vaccinated HCWs demonstrated a higher seroprevalence rate, seroconversion, and GMT. Conclusions: Previous vaccination can influence the immune response, although without substantially compromising the immunogenicity of annual influenza vaccination. HCW annual influenza vaccination is required to re-establish and maintain the antibody titers against influenza. Full article
(This article belongs to the Special Issue Advance Public Health Through Vaccination)
Show Figures

Figure 1

16 pages, 260 KiB  
Article
Knowledge, Attitudes, and Practices towards Influenza Vaccine among Guangzhou Residents: A Cross-Sectional Study
by Jiawen Xu, Jianyun Lu, Qing He, Yu Ma, Keyi Wu, Haowen Chen, Xiaowei Ma and Xianbo Wu
Vaccines 2024, 12(10), 1169; https://doi.org/10.3390/vaccines12101169 - 14 Oct 2024
Viewed by 1160
Abstract
Background: Influenza vaccination is an important prevention strategy for flu illness. However, the vaccination rate is still low in Guangzhou, China. This study aimed to understand the status of knowledge, the attitude towards the vaccines’ reliability and safety, and other aspects associated with [...] Read more.
Background: Influenza vaccination is an important prevention strategy for flu illness. However, the vaccination rate is still low in Guangzhou, China. This study aimed to understand the status of knowledge, the attitude towards the vaccines’ reliability and safety, and other aspects associated with the willingness and practice of influenza vaccines in the pediatric and adult populations of Guangzhou city. Methods: This study was performed in eleven districts in Guangzhou between November 2020 and December 2020, including the Yuexiu, Liwan, Haizhu, Tianhe, Baiyun, Panyu, Huadu, Nansha, Huangpu, Zengcheng, and Conghua districts. The parents of children and teenagers under the age of eighteen in Guangzhou were surveyed using self-administered questionnaires in four domains: demographic information, the knowledge status and perception of influenza vaccination, the willingness and attitude towards influenza vaccination, and previous vaccine uptake. A multivariable logistic regression was employed to assess the possible determinants of willingness and practice to receive influenza vaccination, calculating the odds ratios (ORs) and 95% confidence interval (CI). A two-sided p-value < 0.05 was deemed statistically significant. Results: A total of 13,213 valid questionnaires were collected (validity rate 98.8%). Out of these participants, 42.62% (5631 participants) expressed a willingness to receive the influenza vaccine, while 55.40% (7320 participants) reported that their children and teenagers had been vaccinated against the flu. Furthermore, 40.44% of the respondents (5343 participants) or other family members had received the influenza vaccine. Logistic regression indicated that factors such as being female (OR = 1.395, 95% CI: 1.278–1.522), being involved in the work of COVID-19 prevention and control (1.551, 1.396–1.724), affirming the preventive effects of vaccination (2.474, 2.106–2.906), knowing about annual influenza vaccination (2.756, 2.540–2.992), and understanding prioritized influenza vaccination populations (1.464, 1.343–1.596) were all positively associated with vaccination willingness. Conversely, middle-aged persons (aged 40–49 years old) (0.726, 0.617–0.853), higher educational levels (undergraduate versus middle school) (0.858, 0.768–0.959), heightened concerns about vaccine safety (considering side effects are obvious versus considering it is safe and basically no side effects) (0.284, 0.188–0.429) and lower knowledge scores (0.813, 0.701–0.942) were adversely linked with vaccination willingness. Conclusion: These findings provide essential insights for altering the perception of influence and influenza vaccination, as well as enhancing health communication strategies to improve influenza vaccine uptake among Guangzhou residents. Full article
(This article belongs to the Special Issue Immune Response after Respiratory Infection or Vaccination)
11 pages, 1419 KiB  
Article
Comparison of Predictive Factors of Flu Vaccine Uptake Pre- and Post-COVID-19 Using the NIS-Teen Survey
by Ty J. Skyles, Harlan P. Stevens, Spencer C. Davis, Acelan M. Obray, Dashiell S. Miner, Matthew J. East, Tyler Davis, Haley Hoelzer, Stephen R. Piccolo, Jamie L. Jensen and Brian D. Poole
Vaccines 2024, 12(10), 1164; https://doi.org/10.3390/vaccines12101164 - 12 Oct 2024
Cited by 1 | Viewed by 1350
Abstract
Background: Seasonal influenza vaccination rates are very low among teenagers. Objectives: We used publicly available data from the NIS-Teen annual national immunization survey to explore factors that influence the likelihood of a teen receiving their seasonal flu shot. Methods: Traditional stepwise multivariable regression [...] Read more.
Background: Seasonal influenza vaccination rates are very low among teenagers. Objectives: We used publicly available data from the NIS-Teen annual national immunization survey to explore factors that influence the likelihood of a teen receiving their seasonal flu shot. Methods: Traditional stepwise multivariable regression was used in tandem with machine learning to determine the predictive factors in teen vaccine uptake. Results and Conclusions: Age was the largest predictor, with older teens being much less likely to be vaccinated than younger teens (97.48% compared to 41.71%, p < 0.0001). Provider participation in government programs such as Vaccines for Children and the state vaccine registry positively impacts vaccine uptake (p < 0.0001). Identifying as non-Hispanic Black was a small, negative predictor of teen vaccine uptake (78.18% unvaccinated compared to 73.78% of White teens, p < 0.0001). The state quartile for COVID-19 vaccine uptake also strongly predicted flu vaccine uptake, with the upper quartile of state COVID-19 vaccine uptake being significantly more likely to also get vaccinated for influenza (76.96%, 74.94%, 74.55%, and 72.97%, p < 0.0001). Other significant factors are the number of providers, education of the mother, poverty status, and having a mixed provider facility type. Additionally, the multivariable regression analysis revealed little difference in the predictive factors of vaccine uptake between pre- and post-pandemic datasets. Full article
(This article belongs to the Special Issue Acceptance and Hesitancy in Vaccine Uptake)
Show Figures

Figure 1

Back to TopTop