Vaccines

Objectives To evaluate the impact of COVID-19 vaccination on the prevention of long COVID (LC) in the Omicron era through an updated systematic review and meta-analysis. Methods We performed an update of our previously published systematic review and meta-analysis of vaccination and LC risk (searches between 1 January 2022 and 1 March 2024). Databases (Embase, MEDLINE, PubMed, Europe PMC, LILACS, Cochrane COVID-19 Study Register) were searched for studies published between 1 March 2024 and 13 July 2026. Observational studies assessing the impact of vaccination on the risk of LC four or more weeks after SARS-CoV-2 infection were included. Vaccines were restricted to those centrally authorised in the European Union. Random-effects meta-analyses, restricted to adults, were performed to calculate pooled odds ratios (OR) of LC in three comparisons: vaccinated (any dose) versus unvaccinated; booster vaccination versus unvaccinated; and booster vaccination versus primary course vaccination only. Results Nineteen new studies were identified, of which ten were included in the updated meta-analyses alongside eight studies from the original review. The pooled OR of LC in vaccinated adults (any dose) versus unvaccinated was 0.75 (95% confidence interval [CI] 0.67-0.84; 13 studies). ORs were also lower for booster vaccination versus unvaccinated (0.73; 95% CI 0.65-0.82; 6 studies), and booster vaccination versus primary course vaccination (0.63; 95% CI 0.53-0.75; 6 studies). Significant associations between vaccination and lower LC odds were observed in subgroup analyses of mRNA-only vaccination and LC outcomes three or more months after infection. Conclusions This updated review and meta-analysis reinforces our previous finding that vaccination may reduce the burden of LC in the Omicron era, with booster doses potentially providing additional protection. Although evidence in high-risk groups now prioritised for vaccination in most countries remains limited, these findings clearly demonstrate the benefits of vaccination and support current seasonal vaccination strategies.

Introduction:Although the COVID-19 pandemic clearly showed the potential consequences of a world without vaccinations, vaccine hesitancy is likely to be more pronounced in the post-COVID-19 era. The introduction of human papillomavirus (HPV) vaccines in this context is likely to raise particular concerns. In Tunisia, decision-makers have prioritized the introduction of HPV vaccine into the immunization schedule. This study assessed individual barriers and facilitators to HPV vaccine acceptability in Tunisia, with the aim of guiding an effective communication strategy for HPV vaccination campaigns in Tunisia and neighboring countries in a post-pandemic context.Methods: Using a qualitative design, we conducted 14 focus groups (FG) with healthcare professionals (HCP) (N=32) and community representatives (CR) (N=89) in five regions of the country. The discussion followed a semi-structured guide designed on the basis of vaccine hesitancy determinants matrix. Transcripts were deductively analyzed according to the 'social processes' and 'thinking and feeling' of the behavioural and social drivers (BeSD) Framework. Inductive approach was used to analyze participants suggestions for promoting HPV vaccination.Results:The FG analysis demonstrated that the historically strong trust in vaccination in Tunisia has weakened after the COVID-19 pandemic. Mistrust of health system and experts, the pandemic management and vaccine mandates measures had negative influence on the vaccine attitudes in a post pandemic Tunisian context. Persistent concerns about COVID-19 vaccines safety were frequently intertwined with widespread distrust of pharmaceutical companies and their profit motives, perceived as imposing inequitable access and lower-quality vaccines on countries in the Global South. These concerns fueled confusion about vaccines side effects. The weakening of immunity was recurring, as well as memory issues, impacts on fertility, and sudden deaths. Regarding information, our research revealed that although digital platforms were perceived as widely used, a significant part of the population interviewed considered public TV channel, as the most reliable source of health information.Conclusions: Emphasizing how the pandemic has shaped individual and collective perceptions and attitudes toward vaccination, our findings underline the importance of leveraging lessons learned from the pandemic to develop a context tailored and coherent communication strategy for successful HPV vaccine implementation.

Abstract Background: Cyprus has transitioned into a high-alert zone for mosquito-borne viruses. This necessitates a proactive assessment of its future physicians. Following the 2022 re-establishment of Aedes aegypti in Larnaca and Aedes albopictus in Limassol, Cyprus, the island is now biologically primed for local outbreaks of dengue, Zika, and chikungunya, alongside Culex-borne West Nile virus. The study assessed medical students' knowledge and risk perception. Methods: A cross-sectional online survey administered the validated MosquitoWise Health Belief Model instrument to undergraduate-entry and graduate-entry students at a university in Cyprus in mid-2026. Results: Of 1023 students, 119 responded (11.6%), with pre-clinical students overrepresented (p<0.001). Mean knowledge was 5.43/9, stronger on mosquito biology (72.5%) than virus knowledge (54.2%). Median severity was 6.00/7 against susceptibility 4.25/7. Knowledge differed by study stage (p<0.001), correlated with severity (rs = 0.399) but not susceptibility. Conclusions: The study establishes a critical baseline for pre-clinical medical students in Cyprus. Overall, participants performed better on mosquito biology when compared to mosquito-borne viruses and how they spread. Our findings highlight the value of integrating theoretical microbiology with clinical practice in medical education to enhance physicians' preparedness for the changing landscape of newly emerging infections in Cyprus and across Europe as a whole. Key Words: Arboviruses, Cross-Sectional Studies, Cyprus, Health Belief Model, Medical Students, Risk Perception.

ObjectiveTo assess the knowledge, willingness and barriers to human papillomavirus (HPV) vaccination among caregivers of adolescent girls living with HIV in Sierra Leone. MethodsThis cross-sectional study examined HPV vaccine knowledge, willingness, and barriers among 249 caregivers of adolescent girls living with HIV in Sierra Leone. Data were collected through structured questionnaires at public tertiary hospitals and high-volume HIV clinics, and associations were assessed using chi-square tests, logistic regression, and Kruskal-Wallis analyses. ResultsOnly 32.1% (80/249) of caregivers had heard of HPV, with even fewer aware of its link to cervical cancer (24.4%, 60/246) or prevention methods of cervical cancer (31.9%, 79/248). Misconceptions were prevalent; 16.3% (36/221) erroneously linked oral contraceptives to cervical cancer, and 61.1% (44/72) of caregivers unwilling to vaccinate cited distrust in vaccine efficacy. While tertiary-educated caregivers exhibited the highest level of knowledge (45.5%, p < 0.001), their willingness to vaccinate (50%, 33/66) was comparable to that of less-educated groups, highlighting a knowledge-action gap. Structural barriers dominated, with 66.1% (154/233) citing unawareness of the vaccine and 10.3% (24/233) missing school-based vaccination days. Relationship dynamics significantly influenced willingness: extended family members showed the highest willingness (69.4%, p = 0.029), whereas grandparents were least willing (31%, 9/29). Although systemic gaps such as disrupted vaccination services, vaccine supplies and cold chain limited uptake, healthcare workers emerged as the most effective information source (rank sum = 889.5, p = 0.039). ConclusionThe study highlights the need for culturally tailored education to dispel myths and community-driven strategies engaging trusted actors like healthcare workers and extended families. This study justifies the need for integration of HPV vaccination and cervical cancer screening into HIV care services.

There is currently no clinical data for the effectiveness of the only licensed Ebola virus disease vaccine (Ervebo) against Bundibugyo virus disease. A number of studies have shown immune cross-reactivity with Bundibugyo virus after Ervebo vaccination. However, antibody recognition of Bundibugyo is around 2.8-fold lower than recognition of Ebola virus. Here, we aimed to infer how a 2.8-fold drop in immune recognition may affect Ervebo protection against Bundibugyo virus disease based on analysis of data on Ervebo immunogenicity and protection from Ebola virus disease. This work has three main components. Firstly, we analysed the timing of vaccine protection in the Ervebo pivotal ring vaccination clinical trial. Secondly, we performed a systematic review and meta-analysis of antibody responses to Ebola virus after Ervebo vaccination over time. Thirdly, we combined these data with previously reported data on the cross-reactivity to Bundibugyo virus to infer protection of Ervebo against Bundibugyo virus disease. We find that the clinical trial data for Ervebo supports vaccine protection beginning earlier than 10 days after vaccination. Secondly, binding antibody levels against Ebola virus on day 28 post vaccination (peak responses) were on average 12.9-fold (95% confidence interval, CI: 6.4 - 26.0) higher than on day 7, 6.3-fold (95% CI: 3.7 -10.8) higher than on day 10, and 2.5-fold (95% CI: 1.4 - 4.4) higher than on day 14 (neutralising antibodies showed similar results). Finally, we consider the scenarios where antibody levels to Ebola virus at day 7 or 10 are putative protective thresholds against Ebola virus disease, and we assume these thresholds also apply for Bundibugyo virus disease. Then, with a 2.8-fold reduction of responses to Bundibugyo compared to Ebola virus, we predict antibody responses to Bundibugyo virus after Ervebo vaccination are likely above these putative protective thresholds.

BackgroundSince the COVID-19 pandemic, parental delays and refusals of well-established, safe, and effective childhood vaccinations have contributed to the resurgence of infectious diseases. This raises concerns that COVID-19 vaccine hesitancy may also extend to novel vaccines for children when introduced in the future. This study examined caregivers, who included healthcare workers (HCWs), perceptions of novel vaccinations for children ages 0-17 years old and intentions to vaccinate children and adolescents ages 12-17 years against COVID-19. MethodsWe conducted a secondary data analysis of a larger cross-sectional survey administered to parents/caregivers of children ages 0-17 years in Lusaka, Zambia, between 13 November and 15 December 2023. Vaccination intention for COVID-19 was specifically focused on caregivers of adolescents ages 12-17 years, following COVID-19 vaccination guidelines during the study. Descriptive statistics were used to explore demographic characteristics, vaccination history, and caregivers COVID-19 vaccination status, along with their childrens routine childhood vaccine histories and perceptions of COVID-19 and novel vaccinations. ResultsAmong 277 caregivers (66.8% women, median age: 35 years), 93.1% reported that their child had received all recommended routine childhood vaccinations. COVID-19 vaccine uptake was higher among HCWs (68.2% with [&ge;]2 doses) than among community members (40.8%) and having [&ge;]2 doses was associated with higher COVID-19 vaccine uptake among their adolescents ages 12-17 years. 58.0% of caregivers indicated that their 12-17 years old adolescents had received at least one COVID-19 vaccine dose. Overall intention to further vaccinate children against COVID-19, especially among those already unvaccinated, remained low, with 24.7% of caregivers reporting no intent to vaccinate their children. Protection from hospitalization and death from malaria, TB, HIV, pneumonia, influenza, and diarrheal diseases were the most cited reason (79.1%) for intention to vaccinate children with novel vaccines for these diseases. The most prominent reasons for reluctance towards future vaccines were the fear of potential side effects (45.5%) and insufficient knowledge about vaccination benefits and risks (31.8%). Caregivers most trusted the Ministry of Health (86.6%) and healthcare professionals (66.8%) as sources of vaccine information. ConclusionsWhile routine childhood vaccine uptake remained high, acceptance of COVID-19 and future novel vaccines for children was lower and was influenced by caregivers own vaccination status. Targeted and transparent communication through trusted sources such as the Ministry of Health and healthcare professionals may be critical for addressing safety concerns and strengthening confidence in novel childhood vaccines.

Background: COVID-19 vaccination uptake is influenced by various sociodemographic and psychological factors. Previous studies have suggested that the relationship between personality traits and vaccination is context-dependent. However, this association has not been investigated in Japan, a unique sociocultural context characterized by historically low vaccine confidence but exceptionally high COVID-19 vaccine uptake. We examined the association between the Big Five personality traits and completion of the primary COVID-19 vaccination series, exploring potential gender-personality interactions. Methods: A web-based, cross-sectional survey was conducted among 7,210 Japanese adults (aged 20-85 years) in December 2021. Personality was assessed using the Japanese version of the Ten-Item Personality Inventory. Multivariable Poisson generalized estimating equations were used to calculate adjusted prevalence ratios (PRs) and assess gender-personality interactions. Results: Higher extraversion and lower openness were significantly associated with vaccination completion across genders. A significant gender-agreeableness interaction was observed: agreeableness (PR = 1.016, 95% CI: 1.008-1.024) was positively associated with vaccination completion among men but not women. A similar, though only marginally significant, interaction pattern was observed for neuroticism (PR = 1.011, 95% CI: 1.004-1.019 among men). Conclusions: Personality traits act as modest but meaningful, gender-specific psychological modifiers of vaccination behavior in Japan. Public health campaigns should transition from traditional "one-size-fits-all" messages to personality-tailored and gender-responsive communication strategies to optimize vaccine uptake and bolster psychological resilience in future pandemics.

Importance: Nirsevimab, a monoclonal antibody against RSV, was implemented in France in September 2023. Recently, rare resistance-associated substitutions were described in RSV but the effectiveness according to lineages remains unclear. Objective: We aimed to estimate the effectiveness of nirsevimab against hospitalization for RSV bronchiolitis according to RSV lineages. Design: We conducted a multicenter test-negative case-control study from October 15, 2023 to March 15, 2025. Setting: This study was based on data from three national multicentric prospective studies. The 12 participating centers were secondary or tertiary hospital with a pediatric department located in France. Participants: We included all children younger than 12 months who were hospitalized for RSV bronchiolitis in one of the participating centers in France during the two first RSV epidemic seasons following the implementation of nirsevimab (from October 15, 2023 to February 29, 2024, and from October 10, 2024 to March 15, 2025). Main outcomes and measures: The main outcome of the study was the RSV test result of bronchiolitis cases. RSV whole-genome sequencing was performed using a tiled amplicon approach covering the complete viral genome, as previously described in the POLYRES studies. We estimated the effectiveness of nirsevimab by a multivariable logistic regression model adjusted for potential confounders. We estimated the adjusted risk of immunization failure for each lineage by calculating relative odds ratio to a reference lineage. A range of sensitivity analyses were conducted. Results: We included 3019 infants with bronchiolitis among which 2273 had a positive RSV test (case patients) and 746 had a negative RSV test (control patients). Overall, 373/2273 (16.4%) case patients were immunized by nirsevimab versus 423/746 (56.7%) control patients. The adjusted effectiveness of nirsevimab against hospitalization for bronchiolitis was 88.4% (95% CI, 84.5-91.4) with RSV-B and 79.4% (95% CI, 73.7-83.8) with RSV-A. The risk of immunization failure was 3.2-fold (95% CI 1.8-5.7) higher for lineages derived from A.D.3 than for lineages derived from B.D.4.1. Conclusion and relevance: In this multicentric case-control study, we observed that nirsevimab effectiveness was variable across RSV lineages, with a lower effectiveness against A.D.3 lineages compare to others. Further surveillance is needed to confirm these findings and assess their implication on RSV lineages epidemiology as nirsevimab use expands.

Background: Nigeria introduced single-dose HPV vaccination for girls aged 9-14 in 2023, reaching approximately 60% aggregate coverage by 2025. While an important achievement, this remains short of the 90% coverage called for under the WHO's 90-70-90 cervical cancer elimination targets, and further scale-up depends on reaching out-of-school girls. In this study we used a model of HPV transmission in Nigeria to quantify the residual cervical cancer burden under continued adolescent delivery, assess how additional screening scale-up and equity assumptions modify it, and identify the effective coverage requirements for an infant HPV vaccination program to be non-inferior to the existing adolescent strategy. Methods: We used HPVsim, an agent-based microsimulation calibrated to Nigerian sexual behavior, HPV prevalence, and cervical cancer incidence, to project new cervical cancer cases and age-standardized incidence over 2025-2100 under scenarios which vary vaccination delivery mode (status-quo adolescent, WHO 90-70-90 adolescent scale-up, and 60/75/90% infant delivery), screening coverage (opportunistic 15% vs. scaled 70% aggregate), and the degree to which primary school completion correlated with vaccination (odds ratio 1 vs. 5) and with screening (odds ratio 1 vs. 3). Infant delivery scenarios were run at hypothetical effective-vaccine-efficacy-at-exposure values of 50%, 70%, and 95% - scenario inputs bracketing the plausible waning range, not evidence-based estimates of infant vaccine performance (no HPV vaccine trial has enrolled anyone below age 10). Each scenario was run at 50 replicates (10 calibration draws, 5 seeds); reported outcomes are the median across replicates and uncertainty ranges are interquartile (25th-75th percentile). Results: Continuation of Nigeria's current adolescent program is projected to avert 1.82 million cervical cancer cases (IQR 1.65-1.90 million; 95% UI 1.39-2.02 million) over 2025-2100 (a 53% reduction relative to no vaccination, IQR 51-55%; 95% UI 46-58%), with age-standardized incidence falling from 19.7 to 7.8 per 100,000 by 2100. However, 82% of the near-term (2025-2075) burden is projected to fall on the pre-2015 birth cohort, i.e. women already beyond the vaccination target age, leaving approximately 945,000 residual cases (IQR 905K-1.00M; 95% UI 835K-1.14M) in this cohort. Scaling up screening to WHO targets was estimated to avert a further ~387K cases (IQR 331-424K; 95% UI 269-515K), roughly 25% of the residual burden; results were about 6-8% better if the scale-up instead reached all women equitably regardless of education. Under a hypothetical scenario of infant vaccination at 90% coverage and 95% effective vaccine efficacy at exposure (matching adolescent-age performance), outcomes were comparable to full WHO adolescent scale-up (49% vs. 54% reduction in vaccine-targetable cohort cancers), but under a hypothetical 50% effective efficacy at Nigeria's DTP3-anchored 62% coverage the strategy averted only a fraction of these cancers. Conclusions: The near-term cervical cancer burden in Nigeria is dominated by cohorts vaccination cannot reach; scaling screening for them is the more consequential lever over the coming three decades and rests on established evidence. Findings on infant HPV delivery are exploratory and hypothesis-generating: they depend on three unverified empirical prerequisites - infant HPV vaccine immunogenicity in the first months of life, durability of protection across the ~15-25-year interval to peak HPV exposure, and coverage achievable through Nigeria's routine childhood immunization platform - and should not be read as a basis for any policy recommendation contingent on infant HPV delivery until those prerequisites are established.

Importance: With a recent shift towards summer seasonal predominance of COVID-19 across much of the US, debate continues over optimal COVID-19 vaccination strategies regarding timing (including summer vaccination), eligibility, and dosing frequency. We evaluated the population-level impact of alternative vaccine strategies to inform US and state vaccine policy. Objective: To compare reductions in COVID-19 hospitalizations under different vaccination timing, eligibility, and dosing frequency. Design: Decision analytical model using a stochastic individual-based model of SARS-CoV-2 transmission, calibrated to US COVID-19 hospitalization incidence from May 2024-April 2025. Setting: Simulated US national population, with additional scenarios representing state-level seasonal patterns. Participants: Simulated population of 5 million individuals with US age structure, stratified by risk group (immunocompetent, high risk with comorbid conditions, or immunocompromised). Exposures: Vaccination timing, universal or age- and risk-based eligibility, and dosing frequency, including a hybrid strategy of universal annual vaccination with a second dose for adults [&ge;]65 years and immunocompromised adults (US vaccine policy during the study period). Main Outcomes and Measures: COVID-19 hospitalization risk per 100,000 persons by age-risk group, measured among vaccinated individuals and in the total population. Results: If summer COVID-19 vaccination timing is feasible, annual universal vaccination in July minimized risk (441 [95% UI: 423-463] COVID-19 hospitalizations per 100,000 persons among adults [&ge;]65 years) compared to a counterfactual scenario with no additional vaccination given during the study period (578 [553-601]). If timing does not change, hybrid vaccination minimized risk, followed by semiannual risk-based vaccination (460 [440-487] and 477 [454-499] hospitalizations per 100,000 in adults [&ge;]65 years, respectively). The advantage of summer timing diminished if vaccine coverage decreased by 5-10 absolute percentage points (25-50% relative decrease). The magnitude of benefit from summer-timed vaccination and semiannual doses in the highest-risk groups varied regionally. Conclusions and Relevance: Although annual COVID-19 vaccination has historically been timed for winter transmission, summer vaccination may avert more hospitalizations if coverage is maintained, especially in states with predominantly summer transmission including Western and Southern states. The comparative impact of vaccination strategies, especially the benefit of a semiannual dose in the highest-risk groups, may vary regionally. COVID-19 vaccination timing and eligibility may warrant reconsideration.

Importance: In the US, Human papillomavirus (HPV) related cancers cause significant morbidity and mortality, yet HPV vaccine is underutilized. Vaccination is recommended routinely at age 11-12 years but can be given at 9 years. There is controversy about whether earlier introduction would increase completion of the HPV series before by age 13 years or whether it might decrease rates of delivery of other routinely recommended vaccines at 11-12-years [quadrivalent meningococcal conjugate (MenACWY) vaccine, and tetanus-diptheria-acellular pertussis (Tdap) vaccine]. Objective: To determine whether introduction of the HPV vaccine at ages 9-10 versus 11-12 years, results in earlier median age of series completion (primary outcome) and higher rates of initiation and completion by age 13 years. We also examined the effect of earlier introduction of HPV on rates of Tdap and MenACWY initiation and completion by age 13 years. Design: Two-arm cluster-randomized trial involving 31 pediatric practices in Colorado and California between 10/2021-4/2026. Practices were randomized using covariate constrained randomization within each state to Intervention (introduction of HPV vaccination at ages 9-10) or Control (introduction at ages 11-12). Both study groups received similar annual training about best practices for HPV vaccination with recommended initiation age as the only difference. Results: Age at HPV series completion was substantially earlier in the Intervention group (median 12.2 v. 13.3 years; adjusted hazard ratio [aHR] 2.37; 95% CI 1.94-2.89). Key secondary outcomes were also improved in the intervention group: age at series initiation (median 11.0 v. 11.8 years; aHR 2.19; 95% CI 1.84-2.62), series completion by 13 years (61.6% v. 45.1%; RR 1.37; 95% CI 1.04-1.74), and vaccine initiation by age 13 years (77.1% v. 67.0%; RR 1.15; 95% CI 1.00-1.33). The intervention group was more likely to receive Tdap (aHR 1.47;95%CI 1.13, 1.92) during the trial; receipt of both vaccines by age 13 years did not differ. Conclusions: Earlier introduction of HPV vaccination resulted in earlier age of series completion, and more adolescents initiating and completing the series by age 13 without decreasing rates of other routinely recommended vaccines. Our findings support a preferential recommendation at 9-10 years. Trial registration number: NCT04722822 ClinicalTrial.gov

BackgroundNipah virus (NiV) is a zoonotic pathogen in the Henipavirus genus that causes severe, often fatal disease in humans. The World Health Organization and the Coalition for Epidemic Preparedness Innovations (CEPI) have designated NiV as a priority pathogen with pandemic potential. While CEPI is funding research on medical countermeasures, including vaccines and monoclonal antibodies (mAbs), there remains limited understanding of how at-risk countries will use them. This study aims to address this gap through targeted interviews and demand forecasting for 10 countries: Australia, Bangladesh, Cambodia, India, Indonesia, Malaysia, the Philippines, Singapore, Thailand, and Vietnam. Methodology/Principal FindingsInterviews with country and global stakeholders gathered data on regional sentiment, financing, and affordability. Profiles were developed to summarize each countrys perceived outbreak risk and their likely use of countermeasures. Demand was estimated by integrating these perspectives into models of likely country-level responses to three NiV outbreak scenarios: Expected, Amplified, and Extended. In the Expected scenario, countries focused on reactive use with global annual demand ranging from approximately 800 to 5,000 doses for vaccine-only, mAb-only, and combination interventions. Ring strategies were preferred given outbreak size and infrequency. Demand was highest for vaccine-only and combination interventions, with lower demand for mAbs-only due to affordability concerns and less familiarity in Bangladesh and India. In Amplified and Extended scenarios, countries expanded their responses to include preventive campaigns for healthcare workers and rural populations. These campaigns would require approximately 410,000 and 6,300,000 doses, respectively, if introduced in all 10 countries. Conclusions/SignificanceThis study has revealed existing sentiments regarding Nipah disease and interventions and modeled demand across three outbreak scenarios. Given global annual demand based on current epidemiology, Nipah countermeasure markets are unlikely to be commercially viable solely on routine country-financed demand. Instead, market health will require external financing and stockpile mechanisms to maintain demand between sporadic outbreaks. Author SummaryNipah virus (NiV), which causes severe and often fatal disease in humans, is recognized by the Coalition for Epidemic Preparedness Innovations (CEPI) as a priority pathogen with pandemic potential. In response, CEPI has supported the development of vaccines and monoclonal antibodies (mAb). However, limited evidence exists on how at-risk countries will deploy these medical countermeasures. We interviewed key decision-makers across 10 at-risk countries, along with global experts on NiV, to better understand disease prioritization, financing and affordability considerations, and countermeasure preferences. Interview findings informed the development of a demand forecast in response to Nipah outbreaks of varying intensity. At expected outbreak levels, countries focused their response on reactive strategies given outbreak size and infrequency. As outbreaks grew in size, countries considered expanding their response to include preventive campaigns targeting healthcare workers and at-risk, rural populations. This study provides new insights into country-level perspectives on NiV and medical countermeasures and quantifies expected demand across three outbreak scenarios and 10 countries. Our findings can provide a foundation for the strategic development of an international Nipah countermeasure stockpile, designed to address episodic NiV outbreaks and enhance pandemic preparedness.

Background: Filoviruses, specifically Ebola virus (EBOV), Bundibugyo virus (BDBV), and Marburg virus (MARV), have been the etiologic agents of multiple outbreaks of severe disease in the Democratic Republic of the Congo (DRC). Two EBOV-specific vaccine regimens have been approved for use in outbreak scenarios, including the Ad26.ZEBOV/MVA-BN-Filo (Zabdeno/Mvabea) two-dose vaccine, where the MVA-BN-Filo booster dose contains EBOV, MARV, and Sudan (SUDV) virus glycoproteins (GPs) and the nucleoprotein from Tai Forest virus. While long-term immunogenicity of up to two years has been found in clinical trial settings, limited real-world data exists. Methods: Using a multiplexed immunoassay, samples (n=698 at baseline) collected in Mbandaka, Equateur province, DRC, between September 2023 and October 2024 were assessed for seroreactivity to six filovirus antigens (1 BDBV, 2 EBOV, 2 MARV, and 1 SUDV) at three distinct periods: baseline/pre-vaccination, 6-8 weeks post-first dose (Zabdeno), at booster administration (Mvabea), and one-year post-boost dose. Results: Substantial filovirus seroreactivity was found at baseline, with 48.7% (n=340/698) of individuals being seroreactive to at least one virus antigen. High baseline seroreactivity was found against BDBV GP (31.1%, n=217/698), with lower baseline seroreactivity to EBOV GP (15.5%, n=106/698), comparatively. Overall EBOV GP seroreactivity increased to 66.8% (n=376/563) at one year-post vaccine boost and 57.6% (n=250/434) of participants were seroreactive. Despite the booster dose inclusion of SUDV GP and MARV GP, there were no substantial increases in reactivity against either antigen at subsequent timepoints. Overall filovirus seroreactivity increased at all timepoints for the entire cohort, although filovirus reactivity decreased over the study period for those who were seroreactive at baseline. Findings: These data highlight detection of significantly elevated seoreactivity to EBOV GP following first-dose administration of Ad26.ZEBOV, which remained relatively stable one-year post-booster dose administration. Additionally, this study identifies high levels of baseline seroreactivity to BDBV GP despite no previous documented outbreaks in this region of DRC. These data suggest that vaccination with the Ad26.ZEBOV-MVA-BN-Filo vaccine induces stable seroreactivity against EBOV GP, but not to other filovirus antigens.

Introduction Vaccination against human papillomavirus (HPV) is the most effective strategy for preventing cervical cancer. We evaluated HPV Vaccine Integrated Service Implementation (HPV-VISION), a program aimed at integrating HPV vaccination with adolescent health (AH) services and the Expanded Program on Immunization (EPI) to improve vaccine uptake among girls aged 9 to 14 years in rural Ethiopia. Methods This mixed-methods implementation study was implemented in four woredas testing two models of integrating HPV vaccination into routine health services: integration with EPI and with an AH service package. We used program monitoring data; exit interviews, in-depth interviews, and focus group discussions with adolescent girls and caregivers; key informant interviews; and costing data. We analyzed effectiveness using negative binomial generalized estimating equation models with facility-level monthly HPV vaccinations as the primary outcome. We analyzed exit interview data descriptively across models. We analyzed qualitative data thematically and conducted a costing analysis. Results The HPV-VISION program delivered 25,821 HPV vaccinations from March to August 2025. Adjusting for baseline differences, facilities in the AH model delivered, on average, 34% fewer HPV vaccinations per month compared to those in the EPI model (adjusted IRR: 0.66; 95% CI: 0.51-0.87). Nearly all girls said they would be happy to receive services again at the place they were interviewed (EPI: 94%, AH: 98%). Experience of care was positive overall with individual measures varying across models. The incremental delivery cost (excluding vaccine cost) per vaccinated girl was USD $7.54 in the EPI model and USD $14.28 in the AH model. Conclusion We recommend that HPV vaccine delivery incorporates integration with AH services and routine vaccination to most efficiently reach underserved girls. An optimal mix of integration with the EPI program and AH services should be based on regional HPV vaccination indicators, other AH needs, population demographics, and costs of the models.

We report general acceptance (79.0%) of Ebola vaccination in the Democratic Republic of the Congo (DRC) between 2023-2024 (n=5,062). Acceptance varied significantly by province with acceptance ranging from 47.6% in Kongo Central to 92.1% in Tshuapa province and was highest among healthcare workers. While Ebola vaccine acceptance and disease knowledge are relatively strong nationally in the DRC, regional differences do exist and may impact future vaccine rollout.

Introduction: Acute gastroenteritis (AGE) is a global public health problem and a major cause of mortality in low- and lower-middle-income countries. Human bocavirus (HBoV) is among the viral agents associated with this condition. Therefore, investigating the presence of HBoV in cases of AGE in Salvador, Bahia, as well as its prevalence and circulating strains, is important. Objective: To investigate the occurrence of HBoV infection during an AGE outbreak in Salvador. Methods: A total of 178 samples were analyzed for HBoV using nested polymerase chain reaction (nested PCR), and the amplification products were visualized by agarose gel electrophoresis. HBoV was detected in 5.7% of the samples analyzed. Conclusion: This study contributes to the understanding of HBoV epidemiology as a secondary agent associated with acute gastroenteritis during a norovirus outbreak in Salvador. Continued investigation and identification of the etiological agents involved in outbreaks are essential for evaluating the causes of AGE. These findings also highlight the need for broader diagnostic approaches and the importance of phylogenetic analysis for monitoring and controlling viral infections.

Background: Global oral cholera vaccine (OCV) supply shortages and the retirement of Shanchol necessitate absolute reliance on alternative formulations. We conducted a systematic review and meta-analysis to evaluate the immunogenicity and safety of Euvichol variants compared with the historical Shanchol benchmark. Methodology/Principal Findings: A searched PubMed, Embase, MEDLINE, Scopus, and Cochrane CENTRAL up to May 2026 for randomized controlled trials (RCTs) comparing any Euvichol variant against Shanchol in healthy populations aged [&ge;]1 year. Primary outcomes were vibriocidal seroconversion rates at 14 days post-dose 2 pooled as Risk Ratios (RRs) via Mantel-Haenszel fixed-effects models. Five RCTs comprising 7,253 participants were included. Euvichol formulations demonstrated non-inferior, equivalent seroconversion rates compared with Shanchol for both Vibrio cholerae O1 Inaba (RR 1.00, 95% CI 0.98-1.02; I2=0%) and O1 Ogawa (RR 1.01, 95% CI 0.99-1.04; I2=26%). Log-transformed Geometric Mean Titers confirmed clinical equivalence for Inaba (MD 0.02, 95% CI -0.01 to 0.05) and Ogawa (MD 0.00, 95% CI -0.03 to 0.03). Overall safety was balanced between arms, showing no significant variation in the risk of any solicited adverse event (RR 0.91, 95% CI 0.75-1.11) or specific symptoms including fever (RR 0.84, 95% CI 0.52-1.35). Serious adverse events were rare and uniformly unrelated to vaccination. Conclusions/Significance: Euvichol variants demonstrate immunogenic non-inferiority and interchangeable safety thresholds compared with Shanchol. These findings robustly support the large-scale integration of modern Euvichol-Plus and streamlined Euvichol-S formulations to stabilize global OCV stockpiles.

Introduction: Acute gastroenteritis (AGE) is a cause of childhood morbidity and may be associated with human adenovirus (HAdV) infection. This study aimed to investigate the occurrence of HAdV in fecal samples from children with AGE in Salvador, Bahia, Brazil, as well as to molecularly characterize the identified strains and evaluate their cytopathic effects in cell culture. Methods: A total of 131 samples were analyzed using the nested polymerase chain reaction (Nested-PCR) technique. Molecular characterization was performed through Sanger sequencing and phylogenetic analysis, while Vero cell cultures were used to investigate the occurrence of cytopathic effects. Results: Of the samples analyzed, 13 (9.9%) tested positive for HAdV, while 118 (90.1%) were negative. The highest detection frequency was observed in children aged three years or younger, particularly those under one year of age. Phylogenetic analysis identified variants related to HAdV-F41 and HAdV-B3, revealing genetic differences and distinct clustering patterns compared with reference sequences. In cell culture, cytopathic effects were observed four days after inoculation, although further analyses are required to confirm productive viral replication. Conclusion: These findings demonstrate the presence of HAdV in the samples studied and contribute to understanding its genetic diversity and circulation in Salvador, highlighting the importance of epidemiological surveillance and further studies on its role in the etiology of childhood AGE.

BackgroundTuberculosis (TB), caused by Mycobacterium tuberculosis (MTB), remains a leading global public health challenge. Malnutrition is a major, modifiable driver of this vulnerability to the disease, creating a lethal, bidirectional link with TB. This s review aims to synthesize available evidence to estimate the pooled prevalence of TB and identify associated factors among malnourished children in Ethiopia, providing critical data to guide targeted, integrated public health interventions. MethodsA systematic review and meta-analysis were conducted on studies reporting the prevalence of TB and associated factors among malnourished children in Ethiopia. Electronic databases including PubMed/Medline, EMBASE, CINAHL, ScienceDirect, Academic Search Complete, and Google Scholar were searched. In addition, bibliographies of relevant articles were reviewed, and a search for relevant conference abstracts was performed. Eligible studies were those published in peer-reviewed journals that specifically addressed TB prevalence among malnourished children. A random-effects model was employed to estimate the pooled prevalence of TB and its associated factors. ResultsA total of 746 studies were initially identified through database and catalog searches. Following screening and eligibility assessment, 12 studies were included in the final systematic review and meta-analysis. These studies, published between 2017 and 2024, collectively involved 5,749 participants. The smallest sample size (133) was reported in a study from the Oromia region, while the largest (1,201) was from the Amhara region. The pooled prevalence of TB among malnourished children was estimated at 16%. The highest prevalence (95%) was reported in a study conducted in Addis Ababa, while the lowest (6%) was from Harar. Considerable variation in prevalence was noted across the included studies. ConclusionThis review resulted in the substantial prevalence of TB among malnourished children in Ethiopia, with a pooled prevalence of 16%. This finding highlights the urgent need for integrated healthcare interventions targeting both TB and malnutrition

Background Women living with HIV (WLHIV) have an increased risk of persistent human papillomavirus (HPV) infection and cervical cancer. We evaluated the lifetime health impact and cost-effectiveness of HPV vaccination strategies targeting WLHIV across 13 African countries. Methods We developed an age-structured Markov model of HPV infection and cervical cancer in a closed cohort of 100,000 females, stratified by HIV status, and calibrated it separately for each country to age-specific cervical cancer incidence, cervical cancer mortality, and female HIV prevalence. Six HIV-targeted strategies were compared with routine two-dose vaccination at age 14 years. The strategies either provided a booster dose to previously vaccinated WLHIV or combined a booster for previously vaccinated WLHIV with a three-dose primary catch-up course for previously unvaccinated WLHIV. Interventions were delivered at ages 18 or 24 years under standard- and high-coverage assumptions. Outcomes included cervical cancer cases averted, cervical cancer deaths averted among WLHIV, discounted disability-adjusted life-years (DALYs) averted, additional physical vaccine doses, and incremental costs from the health-system and vaccination-programme perspectives. Results All six strategies generated additional health gains relative to routine vaccination alone. Mean DALYs averted across countries ranged from 8.21 for booster vaccination at age 24 years to 81.36 for high-coverage combined booster and catch-up vaccination at age 24 years. Booster-only strategies produced the greatest health gains per additional physical vaccine dose, whereas the high-coverage combined strategy at age 24 years produced the largest average absolute health gain. However, the relative performance of vaccination at ages 18 and 24 years varied by strategy and country. From the health-system perspective, 68 of 78 country-strategy comparisons were more effective and less costly than routine vaccination after accounting for avoided cervical cancer treatment costs. From the vaccination-programme perspective, all strategies required additional expenditure. Conclusions HPV vaccination strategies targeting WLHIV generated additional health benefits beyond routine adolescent vaccination and were cost-saving in many country-strategy comparisons when avoided cervical cancer treatment costs were included. Booster-only strategies were the most dose-efficient, whereas combined booster and primary catch-up strategies produced larger absolute health gains. The relative performance of strategies delivered at ages 18 and 24 years was context dependent and should not be interpreted as evidence of a universal advantage of later vaccination. Given the limited direct evidence on the clinical effectiveness and duration of protection following HPV booster vaccination among WLHIV, the booster scenarios should be interpreted as exploratory.