Search Results (8,365)

The coronavirus disease 2019 (COVID-19) pandemic has put a renewed focus on the value of vaccines in combatting potentially life-threatening diseases. The primary aim was to conduct a longitudinal study on the dispensing patterns of vaccines (from 2017 to 2021) in a section of the private healthcare sector in South Africa. A descriptive cross-sectional pharmacoepidemiological study on health insurance data covering 5 years was conducted. The study included all vaccines available on the South African market (childhood, adult, travel, and other vaccines). The study population consisted of 3.8 million individuals. The descriptive statistics were calculated. The vaccine-dispensing patterns were distinctly different in 2021 compared to the preceding four years. The COVID-19 vaccine was introduced in 2021 in South Africa. Although the total number of medical insurance scheme members stayed relatively constant, the number of vaccine claims increased approximately seven-fold in 2021 compared to the average for the preceding four years (2017 to 2020). The tetanus and pneumococcal vaccines were the most dispensed bacterial vaccines, whilst the influenza and COVID-19 vaccines were the most dispensed viral vaccines. COVID-19 vaccines accounted for 55.74% of all vaccines dispensed over the 5 years, and for 85.70% of the vaccines dispensed in 2021. An increase in the number of bacterial vaccines dispensed was observed towards the middle of 2020, which was attributed to the pneumococcal vaccine. Pneumococcal vaccines were administered during the COVID-19 pandemic to prevent morbidity and mortality from co-/secondary infections and superinfections. Similar ongoing studies on vaccine-dispensing patterns in the post-COVID-19 era are necessary, especially since the outbreak of various vaccine-preventable diseases has recently been observed. Full article

Background: Long COVID can persist for years, but little is known about its prevalence in relation to the number of infections. This study examines the prevalence of long COVID in association with the number of infections and vaccination status. Methods: We analyzed anonymized data on long COVID cases, thrombotic events and polypharmacy from March 2020, provided by the Data Analysis Control Department for the population assigned to the CST (192,651 at March 2025). Additionally, we analyzed responses to a long COVID symptom-specific survey distributed in March 2024 to individuals aged 18 to 75 years from the CST population diagnosed with COVID-19 as of December 2023 (n = 43,398; 3227 respondents). Symptomatic patients suspected of having long COVID underwent blood tests to exclude alternative diagnoses. Results: The overall detected prevalence of long COVID was 2.4‰, with higher frequency among women aged 30–59 years (p < 0.001). The survey, combined with specific blood tests, improved detection rates by 26.3%. Long COVID prevalence was 3–10 times higher in individuals with three or more infections than in those with only one recorded infection (based on survey/CST data, respectively). The absolute number of thrombotic events among individuals aged >60 doubled from 2020 to 2024, occurring in both vaccinated and unvaccinated individuals, as well as in those with or without prior documented COVID-19 infection, including in patients without chronic treatments. Conclusions: We found a link between SARS-CoV-2 reinfection and long COVID, and a post-pandemic rise in thrombotic events across all populations, regardless of vaccination or prior infection. Findings support continued COVID-19 diagnosis in suspected cases and mask use by healthcare workers treating respiratory patients. Full article

Background/Objectives: The COVID-19 pandemic and the development of vaccines provided the opportunity to monitor disease prevalence and outcomes, vaccinations, their side effects and serological responses in patients with inflammatory bowel disease (IBD). Methods: IBD patients of the outpatient clinic at the University Hospital Heidelberg who completed at least one questionnaire on COVID-19 and related vaccinations from July 2021 to August 2022 were included. Spike-IgG antibody titres were determined. Friedman tests, Wilcoxon signed-rank tests and Kruskal–Wallis tests were used for comparisons. The influence of IBD therapy was analysed using linear models with mixed effects. Results: The cohort included 520 patients (269 females, mean age = 45.3 years, 60.6% with Crohn’s disease, 35.4% with ulcerative colitis, and 4.0% with unclassified IBD). Four hundred eighty patients (92.3%) received at least one COVID-19 vaccination, and 154 patients (29.6%) were infected by SARS-CoV-2. Among all of them, 94.4% achieved seroconversion. Triple-vaccinated patients with additional SARS-CoV-2 infection developed the highest serological responses (χ² = 16.51, p < 0.001, df = 3). An antibody decay over time was observed after the second (p < 0.001) and third vaccinations (p < 0.001). Regarding individual IBD medications, no differences in mean titres were found after two (χ² = 6.60, p = 0.36, df = 6) versus three vaccinations (χ² = 4.97, p = 0.42, df = 5). Linear models with mixed effects revealed no influence of IBD therapies on serological responses. Conclusions: The highest serological responses were observed in IBD patients after three vaccinations plus SARS-CoV-2 infection without significant differences between IBD therapies. Full article

Background: Due to the new COVID-19 vaccine types used in the COVID-19 vaccination program, significant levels of uncertainty and vaccine hesitancy arose due to fears about anaphylactic reactions, especially in patients with allergies. This study aimed to analyze how patients with significant allergies receiving specific immunotherapy (SIT) reacted to COVID-19 vaccines in real life. Methods: We assessed 57 patient charts of individuals with allergies receiving SIT for documented allergies, for their comorbidities, total IgE and tryptase levels, and Hospital Anxiety and Depression Scale (HADS) scores. Questionnaires regarding COVID-19 vaccination status and reported adverse reactions were analyzed. Results: Patients were more frequently male (58%) and had a mean age of 43 years, and the majority (60%) had already experienced an anaphylactic reaction in the past, most commonly to the allergen of the current SIT. In total, 93% received COVID-19 vaccinations. More than half of the patients (57%) reported at least one adverse reaction after COVID-19 vaccination. Out of these patients, 97% reacted in an unspecific way, with symptoms of general illness. One potential allergic reaction, classified as a grade 1 anaphylactic reaction, was documented. The patient with the potential allergic reaction was significantly more concerned before receiving the vaccination and had experienced possible allergic reactions to other vaccinations in the past. The remaining patients with unspecific reactions after vaccination had also experienced such adverse reactions in the past to other vaccinations. Antihistamine premedication was associated with fewer unspecific reactions after COVID-19 vaccination. Conclusions: Vaccinations in patients with significant allergies and prior anaphylactic reactions are, overall, safe. Prior allergic reactions after other vaccinations could be a potential risk for reaction after COVID-19 vaccinations, whereas antihistamine intake could be beneficial in reducing side effects after COVID-19 vaccinations in patients with allergies. Prospective studies on this topic are needed. Full article

Background/Objectives: Multifocal Motor Neuropathy (MMN) and Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) are immune-mediated polyneuropathies often treated with immunoglobulin therapy. They were prioritized for COVID-19 vaccination during the pandemic. However, their immune response following COVID-19 vaccination remains unclear. We investigated short- and long-term immune responses to COVID-19 vaccination in patients with MMN and CIDP compared to controls. Methods: In a prospective observational study, patients with CIDP or MMN and matched controls were followed over 24 months. Controls were age- and sex-matched 1:9. Participants received COVID-19 vaccines in accordance with the Danish vaccination program. Primary outcomes were levels of SARS-CoV-2 IgG antibodies and virus-neutralizing capacity. A positive vaccine response was defined as IgG > 225 AU/mL and neutralizing capacity ≥ 25%. Results: We included 34 patients and 306 matched controls. While baseline SARS-CoV-2 IgG levels were similar, controls exhibited higher IgG levels at 6- (mean difference, 88%; p = 0.008), 18- (91%; p = 0.023), and 24 months (160%; p < 0.001). Neutralization capacity was also higher in controls at 6 (10%, p = 0.004), 18 (7%, p < 0.001), and 24 months (9%, p = 0.002). Despite this, the proportion of vaccine responders did not differ between the two groups after 24 months (p = 0.196). In patients receiving immunoglobulin therapy, IgG levels were lower than in controls at 24-month follow-up alone (56%, p < 0.001); all demonstrated a positive vaccine response. Conclusions: Patients with CIDP and MMN demonstrated a positive humoral response to COVID-19 vaccination. Although IgG and neutralization levels were lower than in controls, all patients receiving immunoglobulin therapy were vaccine responders. Full article

Background: While disparities in vaccine uptake have been well documented, few studies have evaluated the impact of local vaccine programs on COVID-19 outcomes, namely cases, hospitalizations, and deaths. Objectives: Evaluate the impact of COVID-19 vaccine doses coordinated by the Louisville Metro Department of Public Health and Wellness (LMPHW) on COVID-19 outcomes by race across ZIP codes from December 2020 to May 2022 in Jefferson County, Kentucky. Methods: Fixed-effects longitudinal models with ZIP codes as ecological time-series units were estimated to measure the association between COVID-19 vaccine doses and outcomes with time lags of one week, two weeks, three weeks, four weeks, and one month. Models were adjusted for time (week or month of the year) and its interaction with ZIP code. Results: In the one-week lag model, significant negative associations were observed between LMPHW-coordinated vaccine doses and COVID-19 outcomes, indicating reductions of 11.6 cases, 0.4 hospitalizations, and 0.3 deaths per 100 doses administered. Vaccine doses were consistently associated with fewer deaths among White residents across all lags, with an average reduction of 0.2 deaths per 100 doses. No significant associations were found for Black residents. Temporal trends also indicated declines in COVID-19 outcomes when LMPHW’s vaccine administration program peaked, between March and May 2021. Conclusions: Timely uptake of COVID-19 vaccines remains critical in avoiding severe outcomes, especially with emerging variants. Racial disparities in vaccine–outcome associations emphasize the potential need for equitable, community-driven vaccine campaigns to improve population health outcomes. Full article

We aimed to explore SARS-CoV-2 evolution during in vitro neutralisation using next generation sequencing, and to determine whether sera from individuals immunised with two doses of the Pfizer-BioNTech vaccine (BNT162b2) were as effective at neutralising the variant of concern (VOC) Delta (B.1.617.2) compared to the earlier lineages Beta (B.1.351) and wild-type (A.2.2) virus. Using a live-virus SARS-CoV-2 neutralisation assay in Vero E6 cells, we determined neutralising antibody titres (nAbT) against three SARS-CoV-2 strains (wild type, Beta, and Delta) in 14 participants (vaccine-naïve (n = 2) and post-second dose of BNT162b2 vaccination (n = 12)), median age 45 years [IQR 29–65]; the median time after the second dose was 21 days [IQR 19–28]. The determination of nAbT was based on cytopathic effect (CPE) and in-house quantitative reverse transcriptase real-time quantitative polymerase chain reaction (RT-qPCR) to confirm SARS-CoV-2 replication. A total of 110 representative samples including inoculum, neutralisation breakpoints at 72 h, and negative and positive controls underwent genome sequencing. By integrating live-virus neutralisation assays with deep sequencing, we characterised both functional antibody responses and accompanying viral genetic changes. There was a reduction in nAbT observed against the Delta and Beta VOC compared with wild type, 4.4-fold (p ≤ 0.0006) and 2.3-fold (p = 0.0140), respectively. Neutralising antibodies were not detected in one vaccinated immunosuppressed participant and the vaccine-naïve participants (n = 2). The highest nAbT against the SARS-CoV-2 variants investigated was obtained from a participant who was vaccinated following SARS-CoV-2 infection 12 months prior. Limited consensus level mutations occurred in the various SARS-CoV-2 lineage genomes during in vitro neutralisation; however, consistent minority allele frequency variants (MFV) were detected in the SARS-CoV-2 polypeptide, spike (S), and membrane protein. Findings from countries with high COVID-19 incidence may not be applicable to low-incidence settings such as Australia; as seen in our cohort, nAbT may be significantly higher in vaccine recipients previously infected with SARS-CoV-2. Monitoring viral evolution is critical to evaluate the impact of novel SARS-CoV-2 variants on vaccine effectiveness, as mutational profiles in the sub-consensus genome could indicate increases in transmissibility and virulence or suggest the development of antiviral resistance. Full article

This narrative review explains the history of anaphylactic or hypersensitivity reactions, their connection to the cardiovascular system, and Kounis syndrome, which is linked to hypersensitivity. Additional subjects discussed include immunoglobulin E and serum tryptase, common pathways of allergic and nonallergic cardiovascular events, current perspectives on Kounis syndrome, allergic myocardial infarction, allergic angina, and the impact of COVID-19 and its vaccination on Kounis syndrome. Kounis syndrome is a distinct kind of acute vascular disease that affects the coronary, cerebral, mesenteric, peripheral, and venous systems. Kounis syndrome is currently used to describe coronary symptoms linked to disorders involving mast cell activation and inflammatory cell interactions, such as those involving T-lymphocytes and macrophages, which further induce allergic, hypersensitive, anaphylactic, or anaphylactic insults. Platelet activating factor, histamine, neutral proteases like tryptase and chymase, arachidonic acid products, and a range of cytokines and chemokines released during the activation process are among the inflammatory mediators that cause it. Proinflammatory cytokines are primarily produced by mast cells in COVID-19 infections. Mast cell-derived proteases and eosinophil-associated mediators are also more prevalent in the lung tissues and sera of COVID-19 patients. As a modern global threat to civilization, COVID-19 is linked to chemical patterns that can activate mast cells; therefore, allergic stimuli are usually the reason. Virus-associated molecular patterns can activate mast cells, but allergic triggers are typically the cause. By activating SARS-CoV-2 and other toll-like receptors, a variety of proinflammatory mediators, including IL-6 and IL-1β, are released, potentially contributing to the pathology of COVID-19. Full article

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) raced around the world across different populations; there needs to be a consolidated effort to understand the divergence of the epidemiology of SARS-CoV-2. Population-based epidemiological characteristics studies measure the extent of SARS-CoV-2 infection in a country. The current research study was designed to report epidemiological data from Pakistan. For this purpose, 246 SARS-CoV-2-infected patients were included in the study. For SARS-CoV-2 confirmation, viral samples were collected from all the study participants; SARS-CoV-2 infection was confirmed by viral nucleic acid detection using a nucleic acid detection kit. After SARS-CoV-2 confirmation, all the study participants were interviewed for epidemiological data through a detailed questionnaire. The study results showed that the disease ratio was higher between 30 and 59 years (51.21%) of age. The male ratio (55.28%) was higher compared to the female ratio (44.71%). The patients’ illiteracy and low socioeconomic status were 32.52% and 59.75%, respectively. The majority of the patients (97.56%) had cough, smell or taste disturbance (79.67%), or fever (76.42%), and 70.73% had fatigue. For comorbidities, a higher ratio was observed for diabetes (38.61%), hypertension (36.17%), and respiratory disease (16.26%). The vaccination status analysis revealed that 51.21% of patients had not received routine immunizations, and 65.5% were un-vaccinated against SARS-CoV-2. Notably, not a single patient was vaccinated for influenza vaccine. The current research study concluded that SARS-CoV-2 was more prevalent in individuals who were middle aged, male, and had low socio-economic status. The most common symptoms were cough, smell or taste disturbance, and fever. The patients’ vaccination status highlights a critical gap in preventive healthcare and shows the need to strengthen vaccination awareness and accessibility in the population to reduce vulnerability to future outbreaks. Future research should focus on investigating the impact of COVID-19 outcomes on comorbidities such as diabetes and hypertension. Full article

Objectives: The aim of the present study was to better understand the antibody concentrations in healthcare workers (HCWs) from a hospital in Mexico City with a high density of COVID-19 patients. Methods: Up to 243 HCWs were recruited in 2020 and 2022 and were sorted into three groups: hybrid immunity (HI, natural infection plus vaccination), vaccine-induced immunity (VI), and unvaccinated but RT-qPCR negative at the beginning of the pandemic (UV). Peripheral blood and nasopharyngeal swab samples were obtained; additionally, saliva samples were obtained from the UV group. The titers of IgG, IgM, and IgA against the SARS-CoV-2 receptor-binding domain (RBD) and nucleocapsid (NCP) proteins were assessed using an in-house ELISA, and positivity to the virus was determined via RT-qPCR. Results: Most HI and VI participants were positive for serum anti-RBD IgG (92.8% and 100%, respectively), while 26.6% (for HI) and 19% (for VI) were positive for anti-NCP IgG. Regarding serum anti-RBD IgA, the VI and HI groups had positive rates of 87.3% and 66%, respectively. In contrast, the UV group showed a rate of 5.7% but the positivity for IgA in saliva was higher (52% for RBD and 35% for NCP). In addition, the highest antibody titers were obtained for anti-RBD IgG and IgA in the HI and VI groups, respectively. In saliva, the IgA antibody titer was higher for the RBD antigen (1:1280). Conclusions: These results strengthen our understanding of antibody concentrations in HCWs during two critical years of the pandemic in a general hospital with many COVID-19 patients. Full article

Objectives: Sex-based disparities in COVID-19 outcomes are well-documented, with men experiencing greater acute severity and women showing increased vulnerability to post-viral syndromes. However, longitudinal immunometabolic trajectories in vaccinated individuals remain underexplored. In this study, sex-based differences in long-term metabolic, endocrine, renal, cardiovascular, and inflammatory responses were investigated among vaccinated individuals recovering from SARS-CoV-2 infection. Methods: This retrospective single-center cohort study included 426 adults (199 females, 227 males) with PCR-confirmed symptomatic COVID-19 and at least two vaccine doses. Serial assessments were conducted at baseline, 18-, 24-, and 30-month post-infection. Parameters included fasting glucose, HbA1c, lipid profile, thyroid function, renal markers, CRP, D-dimer, fibrinogen, troponin, and hematologic indices. Statistical analyses assessed longitudinal changes and sex-stratified correlations. Results: Fasting glucose and HbA1c levels significantly declined over time, more prominently in males. Glucose correlated with age and BMI only in females. Lipid levels remained largely unchanged, although males had higher baseline triglycerides. Females showed rising TSH levels and persistently lower free T3; males exhibited higher creatinine, urea, and troponin levels throughout. Inflammatory markers declined significantly in both sexes, with males displaying higher CRP and troponin, and females showing sustained fibrinogen elevation and a temporary lymphocyte surge. D-dimer was elevated in females at the 30-month point. Conclusions: Sex-specific physiological recovery patterns were evident among vaccinated COVID-19 survivors. Males exhibited earlier metabolic and cardiac alterations, while females had more persistent endocrine and inflammatory shifts. These findings underscore the need for sex-tailored long-term monitoring strategies prioritizing early metabolic and cardiac screening in men and prolonged immunoendocrine surveillance in women. Full article

Influenza is a serious and global health issue, and it is a major cause of morbidity, fatality, and economic loss every year. Seasonal vaccines exist but are not very effective due to strain mismatches, delays in production, and antigenic drift. This comprehensive overview discusses the current situation of influenza vaccination, including the numerous types of vaccines—inactivated, live attenuated, and recombinant vaccines—and their effectiveness, efficacy, and associated challenges. It highlights the effects of the COVID-19 pandemic on the trends of influenza vaccination and the level to which innovation should be practiced. In the future universal influenza vaccines will be developed that target conserved viral antigens to provide long-term protection to people. In the meantime, novel vaccine delivery platforms, such as mRNA technology, virus-like particle (VLP), and nanoparticle-based systems, and less cumbersome and invasive administration routes, as well as immune responses are also under development to increase access and production capacity. Collectively, these innovations have the potential to not only reduce the global influenza epidemic but also to change the way influenza is prevented and prepare the world for a pandemic. Full article

This study highlights how socio-demographic, information, and government factors play different roles in people’s health during COVID-19 between Asian countries and non-Asian countries by employing the Hierarchical Linear Regression. This study finds that government factors play a more significant role in shaping wellness and happiness in Asian countries, whereas they have a stronger impact on health status in non-Asian countries. Second, information factors—such as knowledge about vaccines, medical professionals, and reliable sources—have a more substantial effect on health status in Asian countries, while they are more strongly associated with wellness and happiness in non-Asian contexts. Third, socio-demographic variables exert a greater influence on overall health outcomes in non-Asian countries compared to Asian countries. In particular, gender, occupation, socioeconomic placement, height, and weight consistently play a significant role across all health dimensions in non-Asian countries, whereas their impact varies across different health domains in Asian settings. Full article

Background/Objectives: The rise in urinary tract infections caused by multidrug-resistant (MDR) bacteria presents a serious public health challenge across the Balkans, a region already burdened by aging populations, healthcare resource limitations, and fragmented antimicrobial surveillance systems. Methods: This review explores the epidemiology, risk factors, and consequences of MDR UTIs, particularly in the context of the COVID-19 pandemic, which significantly accelerated antimicrobial resistance (AMR) due to widespread, inappropriate antibiotic use. Results: The paper discusses region-specific data on resistance trends, highlights the gaps in diagnostic infrastructure, and evaluates emerging clinical strategies including antimicrobial stewardship (AMS), rapid diagnostic technologies, novel antibiotics, and non-antibiotic alternatives such as bacteriophage therapy and vaccines. Conclusions: Policy recommendations are provided to strengthen surveillance, promote evidence-based treatment, and ensure equitable access to diagnostic and therapeutic tools. A multidimensional and regionally coordinated response is essential to curb the MDR UTI burden and safeguard public health across the Balkans. Full article

Background: Respiratory viral infections such as influenza, COVID-19, and respiratory syncytial virus (RSV) are considered as major public health threats in Africa. Despite global advancements in vaccine development, persistent inequities in access, delivery infrastructure, and public trust limit the continent’s capacity to control these diseases effectively. This review aimed at providing insights on challenges, efforts, impacts, and opportunities for the future related to vaccination against respiratory viral infections in Africa. Methods: This narrative review synthesizes the peer-reviewed literature and global health reports to examine vaccination efforts against respiratory viruses in Africa. The analysis focuses on disease burden, vaccine coverage, barriers to uptake, enabling factors, progress in local vaccine production, and strategies for integrating vaccines into national immunization programs (NIPs). Results: Respiratory vaccines have significantly reduced hospitalizations and mortality among high-risk groups in African countries. Nonetheless, key challenges, including limited cold chain capacity, vaccine hesitancy, donor-reliant supply chains, and under-resourced health systems, continue to undermine vaccine delivery. Successful interventions include community mobilization, use of mobile health technologies, and leveraging existing immunization platforms. Emerging initiatives in local vaccine manufacturing, including Rwanda’s modular mRNA facility and Senegal’s Institut Pasteur, signal a shift toward regional self-reliance. Conclusions: Maximizing the impact of respiratory vaccines in Africa requires a multifaceted strategy: integrating vaccines into NIPs, strengthening domestic production, expanding cold chain and digital infrastructure, and addressing sociocultural barriers through community-driven communication. These efforts are essential to achieving vaccine equity, health resilience, and pandemic preparedness across the continent. Full article