Background/Objectives: The bivalent RSVpreF vaccine is effective at preventing respiratory syncytial virus (RSV)-associated lower respiratory tract illness in adults. However, data regarding safety and immunogenicity of RSVpreF in Korean populations are limited. Methods: This was a phase 3, multicenter, placebo-controlled, randomized (2:1), double-blind study in Korean adults 60 years of age and older. Participants received a single 120-μg dose of RSVpreF or matching placebo. Safety endpoints included local reactions and systemic events through 7 days and adverse events (AEs) through 1 month after vaccination, and serious AEs (SAEs) throughout the study. RSV-A and RSV-B serum 50% neutralizing geometric mean titers (GMTs) and geometric mean fold rises (GMFRs) were obtained 1 month after vaccination. Results: Overall, 377 participants received study intervention (RSVpreF, n = 251; placebo, n = 126). Most local reactions and all systemic events were of mild or moderate severity. Injection-site pain was the most frequently reported local reaction (RSVpreF, 12.4%; placebo, 3.2%). The most frequently reported systemic events were fatigue (RSVpreF, 23.1%; placebo, 26.2%) and muscle pain (RSVpreF, 15.5%; placebo, 9.5%). AEs through 1 month after vaccination were infrequent (RSVpreF, 3.6%; placebo, 0.8%); none were considered vaccine related by the investigator. RSV-A and RSV-B neutralizing GMTs increased 1 month after RSVpreF, with GMFRs (95% CIs) from before to 1 month after vaccination of 9.5 (8.51–10.67) for RSV-A and 8.3 (7.37–9.39) for RSV-B. Conclusions: In older Korean adults, RSVpreF had an acceptable safety and tolerability profile and elicited robust RSV neutralizing responses 1 month after vaccination consistent with pivotal phase 3 efficacy trial results. ClincalTrials.gov Identifier: NCT06593587 (date of registration: 9 September 2024).
Objectives: This cross-sectional study characterized HBV serological profiles and associated factors among pregnant women in Nanning to inform targeted MTCT prevention strategies. Methods: A total of 1935 pregnant women were enrolled via stratified cluster random sampling from October 2024 to May 2025. Five HBV serological markers were quantified by chemiluminescence immunoassay. Multivariable analysis identified factors associated with HBsAg, HBsAb, and HBcAb positivity. HBsAb geometric mean concentration (GMC) and ratio (GMR) were calculated. Results: The overall seropositivity rates (with 95% CI) of HBsAg, HBsAb, HBeAg, HBeAb, and HBcAb were 6.98% (5.92–8.20%), 59.48% (57.28–61.65%), 1.50% (1.05–2.14%), 15.50% (13.96–17.18%), and 33.02% (30.96–35.15%), respectively. HBsAg, HBeAb, and HBcAb positivity increased with age. The HBsAb GMC among uninfected pregnant women was 4.63 mIU/mL (95% CI: 3.72–5.75). Rural pregnant women had lower HBsAb seropositivity than urban counterparts. Unvaccinated women or those with unknown vaccination status showed higher HBsAg, HBeAg, HBeAb, and HBcAb positivity, and lower HBsAb seropositivity, compared with vaccinated women. Advanced age, chronic comorbidities, and HBV exposure were risk factors for HBsAg positivity, whereas HBV vaccination was protective. For HBsAb, higher education and vaccination were protective; advanced age, rural residence, chronic comorbidities, and non-medical occupations were risk factors. For HBcAb, advanced age, chronic comorbidities, and HBV exposure were risk factors, while higher education and vaccination were protective. Conclusions: Pregnant women in Nanning have a high HBV prevalence and insufficient immune protection. Targeted prevention strategies for reproductive-age women are urgently needed to reduce vertical transmission risk.
Despite longstanding vaccine availability, human papillomavirus (HPV) remains the most common sexually transmitted infection in the United States and a leading cause of preventable cancers. Additionally, HPV vaccination rates remain below other routinely recommended adolescent immunizations, particularly in rural populations. This study aimed to identify barriers related to healthcare access, socioeconomic conditions, cultural beliefs, and provider–patient communication in rural communities. A bibliographical review of articles published in English from 2020 to 2025 and an analysis of national datasets were conducted to establish trends in HPV vaccination rates. State-level HPV vaccination data for adolescents aged 13–17 years were obtained from America’s Health Rankings and the Centers for Disease Control and Prevention National Immunization Survey-Teen. States were classified as predominantly rural or urban using Rural–Urban Continuum Codes, and mean vaccination completion rates were compared. The mean HPV vaccination completion rate was lower in rural states (60.55%) compared to urban states (67.31%); however, this difference did not meet the selected threshold for statistical significance (p = 0.025). Barriers identified in the literature included reduced access to healthcare, differences in provider communication, socioeconomic constraints, and limited health literacy in rural communities. Of the identified barriers, healthcare provider recommendations emerged as one of the strongest predictors of vaccine acceptance. These findings highlight multilevel determinants contributing to differences in HPV vaccine uptake and underscore the need for targeted, evidence-based strategies to improve vaccine access and coverage in underserved adolescent populations.
Background: COVID-19 vaccines have proven effective in reducing severe disease and mortality from SARS CoV-2 infection. The underlying molecular mechanisms and alterations in the human serum metabolome influencing the effectiveness and development of immunity remain unclear. Methods: Serum samples were collected from 29 healthy individuals at three time points: prior to vaccination (A), post-first dose (B), and post-second dose (C). Untargeted high-resolution (HR) liquid chromatography coupled with mass spectrometry (LC-MS) was performed on these samples. Metabolites showing significant differential abundance at each time point were identified, and both multivariate and univariate statistical analyses were performed to determine changes associated with the pairwise comparisons, priming (A vs. B), booster (B vs. C), and the overall vaccine effect (A vs. C). Vaccination-specific features were determined after excluding metabolites associated with SARS-CoV-2 IgG seropositivity to better isolate vaccine-driven metabolic changes. Bioinformatics, pathway, and network analyses were conducted using Ingenuity Pathway Analysis (IPA) to identify relevant pathways. Results: Our study identified significant metabolic changes across the three time points. A total of 377 metabolites were identified, of which 59 metabolites, including prostaglandins, eicosanoids, and lipids, were shared across all three groups. The majority of these metabolites showed an initial decrease after the first dose, followed by broad upregulation after the second dose. We identified 1 (downregulated), 34 (26 upregulated and 8 downregulated), and 18 (2 upregulated and 16 downregulated) unique metabolites in the priming, booster, and the overall vaccine effect groups, respectively. L-3-hydroxykynurenine was observed to be significantly reduced by the priming dose effect. By contrast, the booster effect showed decreased myo-inositol 1,3,4,5-tetrakisphosphate, while levels of DL-DOPA, 3-methoxytyrosine, and prostaglandin-esterified phospholipids, including PC(P-16:0/PGF1α) and PE(PGF1α/18:0), increased. On the other hand, the overall vaccine effect revealed decreased cyclic AMP and increased 3′-O-methyladenosine levels. These changes were associated with perturbations in arachidonic acid metabolism, glycerophospholipid metabolism, arginine biosynthesis, and steroid hormone biosynthesis. IPA network analysis identified AKT, TP53, EGFR, and cAMP as key dysregulated nodes. Conclusions: Longitudinal metabolomic profiling demonstrated that COVID-19 vaccination induced distinct but interrelated biochemical changes throughout the vaccination course. The priming dose induced a limited set of early metabolic changes, whereas the booster was associated with more significantly changed metabolites that were involved in lipid, bile acid, steroid, amino acid, and nucleotide pathways. Together, these findings indicate that sequential vaccination is associated with dose-dependent systemic metabolic adaptation, with the booster dose having the largest number of dysregulated metabolites.
Background: Sustaining progress toward polio eradication requires not only effective vaccination but also a resilient laboratory network capable of timely poliovirus detection, confirmation, and genetic characterization. In the WHO African region, the African polio laboratory network provides essential virological support for eradication efforts; however, persistent circulating Vaccine-derived Polioviruses (cVDPVs) outbreaks and increasing demands of genomic surveillance continue to challenge laboratory capacity. Despite its critical role, evidence describing the operational performance, adaptive capacity, and evolution of regional polio laboratory network remains limited. This study evaluates the performance and operational experience of the African polio laboratory network in 2025, highlighting contributions to poliovirus detection, genomic surveillance, quality assurance, and outbreak response, while sharing lessons to inform regional public health systems. Methods: A retrospective secondary data analysis was conducted using laboratory surveillance and outbreak databases, supplemented by reviews of programmatic reports. Data were cleaned and harmonized prior to analysis. Descriptive analyses were performed to assess laboratory workload, timeliness indicators, genomic capacity, quality assurance performance, and operational challenges. Qualitative review of programmatic documents was conducted to identify contextual factors influencing performance. Results: In 2025, 77,230 Acute Flaccid Paralysis (AFP) specimens were analyzed across 16 laboratories. Ninety-two percent of specimens met the timeliness target for virus isolation, and 94% met the target for PCR-ITD. Genomic sequencing confirmed 20 cVDPV outbreaks in 10 countries. The establishment of new sequencing laboratories in Uganda and Nigeria reduced turnaround times, and a 2025 expansion plan aimed to build sequencing capacity in 12 additional countries. All laboratories assessed in 2024 for virus isolation, PCR-ITD, and environmental surveillance exceeded quality assurance accreditation thresholds and were rated “Pass”. The pilot implementation of Direct Detection Nanopore Sequencing (DDNS) techniques is expected to further strengthen genomic surveillance. Challenges remain, including stock out of essential supplies, uneven workloads, and infrastructure gaps. Conclusions: The African polio laboratory network has demonstrated sustained capacity, adaptability, and innovation in supporting polio eradication activities in the WHO African region. This study provides evidence on the importance of strengthening laboratory systems, expanding genomic capacity, and maintaining quality assurance mechanisms to support the final phase of polio eradication and broader public health surveillance.
Background/Objectives: Maternal antibodies can inhibit vaccine-specific humoral responses in early life, leaving infants at increased risk for severe disease for vaccine-preventable infections. In the case of SARS-CoV-2, infants under the age of 3 months represented most child hospitalizations, yet there is no approved vaccine for children under the age of 6 months. There is a clear need for effective immunization in early life to prevent infant morbidity and mortality. Here, we established a mouse model to define how maternally derived antibodies shape early-life responses to mRNA vaccination. Methods: Adult female mice were immunized with PBS or 5 mcg of the SARS-CoV-2 mRNA-1273 vaccine via intramuscular injection and paired with a male. Pups from subsequent litters were immunized with PBS or 5 mcg of mRNA-1273 vaccine via intramuscular injection. Peripheral blood and spleens were collected at time points post-immunization. We measured vaccine-elicited anti-Spike IgG in mouse pups exposed or unexposed to vaccine-specific maternal IgG. Results: Spike-specific maternal IgG is detectable at high levels immediately after pup immunization or mock immunization; however, in mock immunized pups, it wanes by three weeks post-pup immunization. Pups born to immunized dams developed Spike specific IgG comparable to pups born to naïve dams. IgG subclass analyses distinguished passively acquired antibodies from vaccine-induced responses. Despite robust binding antibody responses, neutralizing activity against D614G pseudovirus was heterogeneous and did not scale proportionally with IgG titers, showing qualitative differences in early-life humoral immunity. Splenic Spike-specific B cell frequencies and T follicular helper (Tfh) cell responses were detectable in vaccinated pups irrespective of maternal immunization status, with Tfh cell frequencies peaking at day 7 post-immunization in both groups. Conclusions: Using SARS-CoV-2 as a model pathogen, we found that early-life mRNA vaccination can elicit humoral immune responses in the presence of maternal antibodies. Furthermore, the presence of maternal antibody did not inhibit the development of antigen-specific B cells or Tfh cells in the spleen. Our findings support the potential of extending vaccination strategies into early infancy and provide a framework for optimizing mRNA-based vaccine timing and design in the context of maternal immunity.
Background/Objectives: In recent years, researchers have directed considerable attention toward the activation of the T-cell response in the development of vaccines against viral infections, including the tick-borne encephalitis virus (TBEV). A particularly promising approach to developing effective and safe T-cell vaccines involves the use of artificial multi-epitope immunogens. The selection of spacers that link epitopes within a construct can have a significant effect on the immunogenicity of multi-epitope constructs. The objective of this study was to design multi-epitope TBEV immunogens using various spacers and to evaluate their immunogenicity. Methods: The present study involved the design of three multi-epitope immunogens, which were developed based on T-cell epitopes from TBEV proteins. The AG1-ub construct contained optimized alanine spacers, the AG2-ub construct contained GPGPG spacers, and the AG4-ub construct contained no spacers. Three DNA vaccines encoding the designed immunogens were subsequently produced. To assess the immunogenicity of the constructs, BALB/c mice were immunized with the designed DNA vaccines via electroporation. Results: The ELISpot assay demonstrated that DNA vaccines encoding AG1-ub and AG4-ub induced a significant number of IFN-γ-producing cells. The DNA vaccine encoding AG2-ub, a multi-epitope with GPGPG spacers, exhibited low immunogenicity, potentially attributable to inadequate processing or misfolding of the AG2-ub protein, thereby affecting the molecule’s structure. Conclusions: The data provided in this study on the effect of spacers on the immunogenicity of multi-epitope constructs can be used to optimize the design of vaccine candidates. However, further research is needed to assess their clinical potential.
Background/Objectives: Hepatitis A virus (HAV) infection is a relevant biological risk in some occupational settings and has long been discussed as an occupational health concern among municipal waste collection workers. Data on HAV seroprevalence and vaccination history in this occupational group remain limited in Italy. This study investigated HAV seroprevalence, self-reported vaccination history, and factors associated with HAV seropositivity among waste collection workers in Sardinia. Methods: This retrospective cross-sectional study analyzed HAV seroprevalence and self-reported vaccination history among 326 workers in Sardinia, Italy, using occupational health surveillance data (2017–2024). Recorded variables included age, sex, smoking habits, years of service, work setting, vaccination status, and serological results. Chi-square and Mann–Whitney U tests assessed group differences; logistic regression identified factors independently associated with HAV seropositivity. Results: HAV seroprevalence was 44.2%; only 0.9% of participants reported previous HAV vaccination. Multivariable analysis identified older age, but not years of service, as independently associated with HAV seropositivity once age was modeled as a continuous variable—a pattern more consistent with birth-cohort differences in lifetime HAV exposure than with cumulative occupational exposure. Worksite 7 showed a higher prevalence ratio of HAV seropositivity relative to the reference site, but this finding was based on a small subsample and should be considered exploratory; observed worksite-level differences may reflect organizational rather than geographic factors. Conclusions: Older age, rather than occupational tenure, was independently associated with HAV seropositivity among Sardinian waste workers, a pattern consistent with birth-cohort differences in lifetime exposure. The high seroprevalence and very low vaccination uptake highlight the need to strengthen prevention through improved vaccination access, awareness, and better integration of occupational and public health strategies.
Background: Over the past decade, the East New Britain Provincial Health Authority in Papua New Guinea has worked with partner research organisations to implement data-driven interventions to improve immunisation coverage. This paper reports on facility assessments conducted as part of a cross-sectional study to understand improvements and identify enablers and barriers to routine childhood immunisation in the province. Methods: Between May and August 2023, nine urban and rural health facilities, providing immunisation services at the time of the study in five areas, were assessed using an adapted World Health Organisation (WHO) Service Availability and Readiness Assessment tool. The tool evaluated facility characteristics, routine childhood immunisation readiness and vaccine supply data. Data were analysed using descriptive statistics and findings were mapped to adapted WHO health system categories to identify service delivery improvement priorities. Findings: Several aspects of immunisation service availability and quality had improved since an assessment in 2016/17. Strengths included fixed-facility and outreach service models tailored to catchment populations, high availability of cold chain and vaccine administration equipment, improved immunisation guidance and job-aids. Priority areas included increasing workforce capacity, improving health record completion to inform outreach, increasing availability of guidelines and reporting tools, reducing stock-outs and enhancing stock tracking. Conclusions: Offering accessible vaccination at every opportunity and using quality data to inform programme implementation and resource allocation are priorities for the Provincial Health Authority. This facility-level assessment identified existing immunisation delivery strengths and highlighted community- and provincial-level priority investment areas to strengthen facility capacity and routine immunisation service delivery.
Background/objective: Older adults experience a disproportionate burden of severe influenza. In the P303 trial (NCT058279789), mRNA-1010 showed greater immunogenicity versus high-dose inactivated influenza vaccine (HD-IIV4) in adults ≥65 years of age. Here, we used a correlate-of-protection framework to estimate the relative VE (rVE) of mRNA-1010 compared with HD-IIV4. Methods: A sigmoidal function was used to model the relationship between geometric mean haemagglutinin assay inhibition (HAI) titers (GMTs) and vaccine efficacy (VE) using data from the P304 trial (NCT06602024), which compared mRNA-1010 and the standard-dose IIV4 in adults ≥50 years of age. The model was then applied to GMTs from the P303 trial to estimate rVE of mRNA-1010 vs. HD-IIV4 in adults ≥65 years. Temporal waning and weighting of case distributions were incorporated to provide a season-integrated estimate. Simulations were performed for three influenza seasons (A/H1N1-dominant, A/H3N2-dominant, and balanced), with a sensitivity analysis varying vaccination and epidemic peak timing. Results: At Day 29, rVE for mRNA-1010 vs. HD-IIV4 was 24.1% (95% CI: 18.2–29.5%) against A/H1N1, 14.5% (8.3–20.3%) against A/H3N2, and 21.0% (16.0–25.8%) against B/Victoria. The season-integrated rVE was 12.4% (3.4–21.3%) across all three strains, with point estimates ranging from 11.6% to 12.6%. Similar findings were seen across simulated seasons, with rVE estimates ranging from 8.8% to 14.3% when varying vaccination timing, peak timing, and strain dominance. Conclusions: Based on this CoP framework, mRNA-1010 was projected to have higher VE than HD-IIV4 in adults ≥65 years of age across a range of simulated epidemiological conditions.
Objective: To evaluate the association between 9-valent human papillomavirus (HPV9) vaccination and the risk of new-onset juvenile idiopathic arthritis (JIA), with particular attention to sex-specific differences, including the relative lack of evidence in males and the potential impact of the COVID-19 pandemic. Patients and Methods: Using the TriNetX U.S. Collaborative Network (2016–2023), children aged 9–13 years who received HPV9 vaccination were compared with unvaccinated controls in prepandemic and pandemic periods. Incident JIA was assessed using matched cohort analyses and time-to-event methods. Results: Similar sex-specific patterns were observed across both periods. HPV9 vaccination was associated with a lower risk of JIA among girls (HR = 0.45 95% CI = 0.22–0.95 in prepandemic and HR = 0.36 95% CI = 0.17–0.74 during pandemic period), while no increased risk was observed among boys (HR = 1.57 95% CI = 0.67–4.05 in prepandemic and HR = 1.14 95% CI = 0.56–2.34 during pandemic period). Among unvaccinated individuals, girls consistently exhibited a higher incidence of JIA than boys. The COVID-19 pandemic did not alter these associations. Conclusions: HPV9 vaccination was not associated with an increased risk of JIA in either sex. A consistent sex-specific pattern was observed across both study periods, with a lower risk of JIA among vaccinated girls but not boys. This finding suggests a potential sex difference in the association between HPV9 vaccination and JIA and warrants further investigation. However, residual confounding, including healthy-vaccinee bias and differences in healthcare utilization, cannot be fully excluded.
The authors would like to make the following corrections to this published paper [...]
Aquaculture has rapidly emerged as one of the fastest-growing industries, supplying nearly half of all aquatic food products intended for human consumption [...]
Background/Objectives: Respiratory syncytial virus (RSV) causes substantial morbidity and mortality in older adults, and in Mexico’s rapidly growing older-adult population it may place increasing pressure on hospital-based care; however, Mexico-specific evidence to inform adult RSV immunization policy remains limited. This study estimated the long-term clinical and economic burden of medically attended RSV among adults aged 60–99 years in Mexico and evaluated the health impact and cost-effectiveness of a year-round RSVpreF vaccination program. Methods: A population-based Markov cohort model compared the RSVpreF vaccination with no vaccination in a hypothetical Mexican cohort aged 60–99 years over a lifetime horizon. Outcomes included RSV-related hospitalizations, emergency department (ED) and physician office (PO) encounters, in-hospital deaths, life-years (LYs), and quality-adjusted life-years (QALYs). Analyses were conducted from Mexican healthcare system and societal perspectives in 2025 Mexican pesos (MXN$) and US dollars (US$), with costs and outcomes discounted at 5% annually. One-way and probabilistic sensitivity analyses and scenario analyses assessed the robustness of the findings. Results: With 58% uptake, RSVpreF reduced hospitalizations by 187,825, ED encounters by 178,278, PO encounters by 465,976, and RSV-related deaths by 15,384. In the first 5 years, hospitalizations, ED encounters, and deaths declined by 31% each, and PO encounters by 14%. Over the lifetime horizon, vaccination generated an additional 96,227 discounted LYs and 71,526 discounted QALYs, while avoiding MXN$ 19,484 million (US$ 1061 million) in direct medical costs and MXN$ 3324 million (US$ 181 million) in indirect costs. Conclusions: Year-round RSVpreF vaccination in Mexico among adults aged 60–99 years could substantially reduce medically attended RSV cases and RSV-related mortality and is projected to be cost-effective, thereby supporting the adoption of preventive strategies to address the growing clinical and economic burden of RSV in Mexico’s aging population.
Background: Pharmacovigilance systems have flagged possible associations between mRNA COVID-19 vaccination and systemic autoimmune inflammatory rheumatic diseases (AIRDs), generating uncertainty for rheumatologists counselling patients. As the first population-scale deployment of an mRNA vaccine platform, COVID-19 vaccination provides a unique setting to examine whether autoimmune safety signals detected in spontaneous reporting systems correspond to measurable disease risk. We synthesised pharmacovigilance and population-based evidence on incident EULAR-defined systemic AIRDs after mRNA COVID-19 vaccination and assessed whether disproportionality signals were corroborated by analytical studies. Methods: We conducted a PRISMA 2020-compliant systematic review searching MEDLINE, Web of Science, Scopus, Embase, and the Cochrane Library from 2019 to April 2026, supplemented by medRxiv and trial registries. Eligible studies included pharmacovigilance disproportionality analyses and analytical studies, including cohorts and randomised controlled trials, evaluating BNT162b2 or mRNA-1273 in adults without known pre-existing autoimmune disease. Risk of bias was assessed using READUS-PV, ROBINS-I, and RoB 2. Meta-analysis was not performed because of substantial heterogeneity. Results: Fourteen studies were included: seven pharmacovigilance studies and seven analytical studies. Disproportionality analyses suggested increased reporting of selected AIRDs, most consistently polymyalgia rheumatica and giant cell arteritis, mainly when all other adverse-event reports served as comparators. These signals were largely neutral when influenza vaccines were the reference. Across analytical studies, associations were inconsistent; modest increases in systemic lupus erythematosus appeared only in selected analyses. Long-term evidence was scarce: only four studies, from three countries (South Korea, Israel, and Norway), followed participants for up to approximately one year, and three of these reported at least one positive association—systemic lupus erythematosus, post-booster rheumatoid arthritis, and polymyalgia rheumatica in older adults—whereas studies restricted to risk windows of three months or less reported no increase. Conclusions: The available evidence does not indicate a consistent increase in incident systemic AIRDs after mRNA COVID-19 vaccination. Although pharmacovigilance studies identified comparator-dependent signals for selected diseases, particularly polymyalgia rheumatica and giant cell arteritis, these findings were generally not confirmed in comparative population-based studies and should be considered hypothesis-generating. Delayed-onset disease remains poorly characterised, and studies with at least one year of follow-up are needed.
Background/Objectives: Seasonal influenza vaccination (SIV) coverage remains suboptimal among adults aged ≥50 years, and the COVID-19 pandemic might influence the determinants of SIV uptake. This systematic review aimed to identify determinants of SIV uptake among adults aged ≥50 years during and after the COVID-19 pandemic. Methods: We searched PubMed, MEDLINE, Embase, Web of Science, Global Health, CINAHL, Cochrane Library, APA PsycINFO, and APA PsycArticles for studies published between 1 December 2019 and 1 January 2026. The pooled prevalence of SIV uptake was synthesized using random-effects models in meta-analysis. Results: A total of 50 studies were included in the systematic review. COVID-19-related factors, such as perceived risk of co-infection with SARS-CoV-2 and seasonal influenza and concerns about potential interactions between COVID-19 vaccines and SIV, were determinants of SIV uptake. Other modifiable determinants included those that existed before the pandemic (e.g., knowledge and perceptions of seasonal influenza and SIV). Subgroup analysis showed that cost and inaccessibility were barriers to receiving SIV in places without a fully subsidized SIV, and perceived susceptibility and vaccine safety concerns were commonly identified as facilitators and barriers in studies with data collected after the pandemic. The pooled prevalence of SIV uptake among adults aged 50 years or above was 53% (95% confidence interval: 44–62%). Such uptake appeared lower among adults aged 50–64 years, in regions without a fully subsidized SIV, and after the COVID-19 pandemic. Conclusions: These findings could inform service planning and interventions promoting SIV uptake among adults aged ≥50 years in the post-pandemic era. More studies are needed to explore determinants specific to people aged 50–64 years to inform health promotion tailored to their needs.
Background: Despite the increasing availability of tailored vaccines, vaccine-preventable respiratory diseases (VPRDs), including influenza, respiratory syncytial virus (RSV), COVID-19, and pneumococcal disease (PD), continue to impose a significant health and economic burden. This study assessed the epidemiological and economic burden of VPRD among adults aged ≥65 across four Nordic countries (Denmark, Sweden, Norway, and Finland). Methods: Data on incidence, hospital admissions, and mortality were obtained from national statistics (week 21, 2024–week 20, 2025) and supplemented with peer-reviewed literature. A static model was developed to quantify epidemiological and economic burden associated with VPRD during the 2024/2025 winter season. Results: During the 2024/2025 season, VPRD resulted in approximately 830,000 symptomatic cases, 60,300 hospital admissions, and 7750 deaths across the Nordic countries. COVID-19 showed the highest estimated incidence and numbers of hospital admissions, followed by influenza, PD, and RSV. Mortality was comparable between COVID-19 and influenza, followed by PD and RSV. Annual healthcare costs were approximately €1132 million, with productivity losses constituting an additional 7%. Conclusions: Despite national vaccination efforts, VPRDs remain a major health and economic burden in the Nordic countries. Strengthening immunization programs through improved vaccine uptake, broader coverage, and use of advanced vaccines may contribute to further reducing this burden.
Bovine neonatal diarrhea (BND) is a leading cause of morbidity and mortality in pre-weaned calves. Commercial maternal vaccines targeting bovine rotavirus (BRV), bovine coronavirus (BCoV), and enterotoxigenic Escherichia coli (ETEC) have been available for decades, yet field outbreaks continue in vaccinated herds. This review examined peer-reviewed literature published between January 2019 and March 2026, identified through a structured PubMed search supplemented by reference-list screening. For BRV, a field strain sharing its VP7 genotype with a vaccine component was not neutralized by vaccine-induced antiserum, indicating that genotype concordance does not predict serologic coverage. For BCoV, hemagglutinin-esterase variation and regional lineage divergence indicate surface-protein evolution, although data linking these changes to reduced efficacy are not available. For ETEC, adhesin diversity and antimicrobial resistance affect both vaccination strategy and case management. Maternal vaccination retains biological value, but field performance is constrained by colostral variability, incomplete passive transfer, and product-to-product immunogenic differences. For all three pathogens, antigenic divergence from vaccine strains is located at individual epitopes, receptor-binding domains, or adhesins rather than at the level of whole-pathogen identity. Subunit and multi-epitope antigen designs, for which proof-of-concept constructs have been reported, operate at this level, and their selection requires characterization of candidate antigens for efficacy, diversity, polymorphism, and cross-protective breadth. Such antigen improvements address the pathogen-side gap but not the passive-transfer and mucosal constraints. Functional surveillance to guide antigen updating, field trials that measure passive-transfer efficiency, and adjunctive strategies are identified as priorities for BND control.
Background: C scales are important measures that can support the vaccination process by analysing the possible reasons for vaccination hesitancy. In some studies, it is not possible to utilise typical models based on the traditional 3C–7C scales, but it is possible to adjust them by using modified proxy measures and converting individual determinants into variables of similar significance in the logistic regression analysis of a vaccination behavioural model. Objective: The aim of this study was to compare the relationship between determinants defining a vaccination behaviour model based on the classic 3C, 5C, and 7C scales with modified proxy measures and two variables (low vaccine-related fear instead of complacency and exposure to misinformation-prone digital sources instead of conspiracy) and the dependent variable, namely, the vaccination status of patients of primary care centres in Poland from 2024 to 2025. Methods: A cross-sectional study was conducted using a survey and questionnaire data linked with patient records from three Polish health centres (N = 1206, 46.9% rural residents and 53.1% city residents). Demographic data and determinants of three vaccination behaviour models were compared between vaccinated and non-vaccinated patients using Pearson’s χ2 test, while behavioural models based on the 3C, 5C, and 7C scales describing the relationship between independent variables and vaccination status (dependent variable) were prepared using logistic regression. Two of seven determinants were changed. Results: All determinants used in the three logistic regression behavioural models differed significantly between vaccinated and non-vaccinated patients (p < 0.001). Furthermore, independent variables in each behavioural model were significantly related to the dependent variable (p < 0.001). With an increasing number of model determinants, Nagelkerke’s R2 increased from 0.303 to 0.435 and the ROC-AUC from 0.828 to 0.882. However, the VIF value indicated very low multicollinearity of determinants. The Wald test did not reveal a significant relationship between confidence in public health and the dependent variable (p > 0.05, OR 1.17–0.92 for Models 1 and 3, respectively). Conclusions: In the vaccination behavioural models prepared based on empirical data, all determinants were found to be significantly related to the dependent variable. As the number of independent variables in the behavioural model increased, parameters such as the ROC-AUC and Nagelkerke’s R2 also increased, while the Akaike information criterion, which determines the balance between fitting the model to data and its complexity, decreased. No significant individual relationship was found for the determinant “confidence in public health”, but this result confirms observations from other previous studies describing the impact of pandemic fatigue, misinformation, and conflicting expert information on institutional trust.
