A 20-year study of incidence trends of anogenital warts in Denmark -population impact of human papillomavirus vaccination.

Beyond measuring coverage: how timeliness could transform routine childhood vaccination programmes.

The National Immunization Survey-Child monitors coverage with recommended routine childhood vaccines. For data collected in survey year 2024, which include children born in 2021 and 2022, the household response rate (23.4%) and availability of adequate provider data for children with completed interviews (51.4%) were comparable to those from earlier survey years. For most vaccines, coverage by age 24 months was similar among children born in 2021 and 2022 and those born in 2019 and 2020. Declines in coverage of 1-2 percentage points were observed for the primary series of Haemophilus influenzae type b conjugate vaccine, the birth dose of hepatitis B vaccine, ≥4 doses of pneumococcal conjugate vaccine, and rotavirus vaccine. Coverage with ≥2 doses of influenza vaccine by age 24 months decreased from 61.0% among children born during 2019-2020 to 53.5% among those born during 2021-2022. Coverage was lower among Vaccines for Children (VFC) program-eligible children than among those who were not VFC-eligible and differed substantially by jurisdiction. Compared with non-Hispanic White children, coverage with many vaccines was lower among non-Hispanic Black or African American and Hispanic or Latino children; coverage was highest among non-Hispanic Asian children. Coverage was also lower among children living in poverty and those living in more rural areas. Maintaining high levels of vaccination and improving coverage among groups and in areas in which rates have declined could help protect children from vaccine-preventable morbidity and mortality. The Community Preventive Services Task Force recommends several interventions to increase vaccination, including standing orders for vaccination, immunization information systems, and vaccination programs in organized child care centers and in Special Supplemental Nutrition Program for Woman, Infants, and Children settings. Other factors demonstrated to be effective include strong provider recommendations, targeted messages from credible and trusted sources, and increased participation in the VFC program.

To assess the cost-effectiveness of including varicella vaccination in the Swedish national vaccination programme for children together with the added impact of catch-up vaccination of susceptible older children. An epidemiological transmission model was used to assess the cost-effectiveness of a two-dose national varicella vaccination programme, with and without a catch-up strategy, compared to no varicella vaccination. Parameter estimates were based on scientific publications and data from Swedish national and regional registries. A national varicella vaccination programme would result in health gains and cost-savings from a societal perspective. Cost-savings were primarily due to a reduction in caregiver productivity loss. From a health system perspective, the cost per quality-adjusted life-year gained was estimated at around SEK 200 000 (EUR 18 000), both with and without catch-up vaccination. At a negotiated vaccine price reduction to 30% of the current list price, the cost per quality-adjusted life-year gained would come down to SEK 5 000 (EUR 450). Our analyses suggest that inclusion of varicella vaccination in the national vaccination programme for children would be a cost-saving strategy from a societal perspective, which together with a catch-up vaccination offer for susceptible older children would result in a fast decline of varicella in Sweden.

This JAMA Forum discusses changes under the Trump administration to the vaccination schedule, oversight of vaccine safety, the National Vaccine Injury Compensation Program, and the Vaccines for Children program.

Pneumococcal conjugate vaccines (PCVs) were implemented in the childhood vaccination program of the Community of Madrid (CM) in 2007, but despite very high vaccination coverage since then, increasing trends in invasive pneumococcal disease (IPD) have been observed in recent years. Epidemiological, clinical, and microbiological data from the Notifiable Disease Surveillance System on IPD cases in children aged 0-17 years in the CM during the period 2007-2024 were analysed. A descriptive analysis was conducted by sex, age-group, clinical presentation, laboratory results, prior vaccination, and antibiotic resistance. Incidence rates (IRs) and IR ratios (IRRs) were calculated overall and by serotypes (STs) covered by each vaccine and the most relevant STs using 2015-2019 as reference period. Between 2007 and 2024, 1,856 cases of IPD were notified: 1,052 (56.7%) in boys and 804 (43.3%) in girls. By age-group, there were 431 cases (23.2%) in < 1 year, 994 (53.6%) in those aged 1-4 years, and 431 (23.2%) in those aged 5-17 years. PCV7, PCV13, PCV15, and PCV20 vaccine included STs IRs increased 7.0, 2.9, 2.3, and 1.5 times, respectively (all P < 0.05), in 2024. STs 24A, 14, 15A, 10A, and 3 IRs also increased (IRRs: 30.5, 17.8, 2.8, 2.7, and 2.6, respectively; all P < 0.05). No strains of the STs 1, 5, or 7F were detected in 2024, and STs 19A decreased to 2.2%. IRs for children and adolescents increased between 2022 and 2024 in the CM, associated to the rise of some PCVs STs, as ST14, while the still persistent ST3 started to decline after 2022.

Rotavirus is an unpleasant, highly contagious viral infection with variable degrees of severity. Although the disease can affect any age, it is predominantly an illness affecting young children. Prior to the development of vaccines, the disease was responsible for many deaths and hospitalisations around the world. Rotavirus is now part of the vaccination programme for children and, since its introduction, hospitalisations and deaths have reduced, not only in the UK but worldwide. This article provides nurses and non-medical prescribers with insight into this disease highlighting the importance of vaccination uptake, with the aim of reducing further the potentially adverse outcomes associated with the condition.

Since 2019, PCV13 has replaced PCV10 in Belgium's childhood vaccination program, reducing IPD cases caused by PCV13 serotypes, mainly 19A, but accompanied by serotype replacement. This changing epidemiology prompted consideration of the higher-valent PCV20 vaccine. Despite broader serotype coverage, clinical effectiveness against certain serotypes remains uncertain, raising concerns about vaccine failures. To date, vaccine failures and breakthrough infections have not been systematically studied in Belgium. This study aims to establish a baseline by characterizing vaccine failures and breakthrough infections in children 0-5years old during the recent PCV13 era, providing a reference point ahead of PCV20 introduction. We conducted a retrospective cohort study including children ≤5years diagnosed with IPD in Belgium from 2019 to 2024, using surveillance data from the National Reference Centre for invasive pneumococci and the PediSurv network. Vaccine failures and breakthrough infections were identified and characterized by serotype and clinical characteristics. Of 543 pediatric IPD cases with known vaccination status, 451 (83%) had received at least one dose of pneumococcal conjugate vaccine. Among these, we identified 26 vaccine failures (5.8%) and 37 breakthrough infections (8.2%). Differences in breakthrough proportions between PCV10 and PCV13 were primarily driven by PCV13-exclusive serotypes, after adjustment no significant differences remained. Vaccine failures were caused by serotypes 19A (61.5%), 3 (26.9%), and 14 (11.5%), and were associated with older age (OR: 1.49; 95% CI: 1.18-1.89) and invasive pneumonia (OR: 3.89; 95% CI: 1.66-9.12). Breakthrough infections involved serotypes 19A (70.3%), 3 (13.5%), 14 (13.5%), and 19F (2.7%) and occurred more often in younger children (OR: 0.61; 95% CI: 0.42-0.87). These findings provide the first national baseline of vaccine failures, offering a reference point for evaluating PCV20 introduction. Continued monitoring will be essential to assess the real-world impact of higher-valent pneumococcal vaccines and to guide evidence-based vaccination policy.

Background: Hepatitis B virus (HBV) infection surveillance is essential to gauge progress toward elimination, assess success identifying/treating cases, and evaluate prevention strategies. Canadian surveillance relies primarily on case detection. Data on undiagnosed HBV infection prevalence are limited. We explore the insight blood donors can bring to surveillance. Methods: Drawing upon the authors’ expertise, operational knowledge, and published literature, we identified key topics to evaluate blood donor data. We then synthesized the relevant data and publications to propose unique insight gained from blood donor data. Results: Annually there are over 100,000 first-time donors; all are tested for anti-HBc, HBsAg, and HBV NAT. The infection rate (HBsAg- and/or NAT-positive) is about 70/100,000 donors, several-fold lower than general population estimates, and has decreased over the past two decades, consistent with an impact of vaccination programs and similar to the general population. Also similar to the general population, HBV infections are more common in Asian, Arab, and Black donors. There are a range of genotypes, with A and D more common in donors than in referred patients. Vaccine-age-eligible donors have lower chronic and resolved hepatitis B prevalence than vaccine-age-ineligible donors. Conclusions: Blood donors are an underutilized source of hepatitis B surveillance data that can lend unique insight into a low-risk population unlikely to be tested in clinical settings. Such data could supplement case detection surveillance. The impact of childhood vaccination programs is evident in adult blood donors. Blood donor residual specimens may be suitable for HBV vaccine–related serosurveillance.

Background: Hepatitis B virus (HBV) infection surveillance is essential to gauge progress toward elimination, assess success identifying/treating cases, and evaluate prevention strategies. Canadian surveillance relies primarily on case detection. Data on undiagnosed HBV infection prevalence are limited. We explore the insight blood donors can bring to surveillance. Methods: Drawing upon the authors’ expertise, operational knowledge, and published literature, we identified key topics to evaluate blood donor data. We then synthesized the relevant data and publications to propose unique insight gained from blood donor data. Results: Annually there are over 100,000 first-time donors; all are tested for anti-HBc, HBsAg, and HBV NAT. The infection rate (HBsAg- and/or NAT-positive) is about 70/100,000 donors, several-fold lower than general population estimates, and has decreased over the past two decades, consistent with an impact of vaccination programs and similar to the general population. Also similar to the general population, HBV infections are more common in Asian, Arab, and Black donors. There are a range of genotypes, with A and D more common in donors than in referred patients. Vaccine-age-eligible donors have lower chronic and resolved hepatitis B prevalence than vaccine-age-ineligible donors. Conclusions: Blood donors are an underutilized source of hepatitis B surveillance data that can lend unique insight into a low-risk population unlikely to be tested in clinical settings. Such data could supplement case detection surveillance. The impact of childhood vaccination programs is evident in adult blood donors. Blood donor residual specimens may be suitable for HBV vaccine–related serosurveillance.

Cancer development is increasingly recognized as a life-course process influenced by early-life exposures and nutritional status. During critical periods of growth and development particularly first 1000 days, biological systems are particularly susceptible to carcinogenic insults and epigenetic modifications that may predispose individuals to malignancy later in life. Deficiencies in key nutrients such as folate and vitamin D can impair DNA repair and immune function, while early exposure to environmental toxins and pollutants contributes to genomic instability and endocrine disruption. Additionally, persistent infections—including Hepatitis B (HBV), Human papillomavirus (HPV), and Helicobacter pylori infection—play a significant role in infection-related cancers, particularly in low- and middle-income countries. Socioeconomic disparities further exacerbate these risks by limiting access to nutrition, healthcare, and preventive interventions. Addressing these early determinants through integrated public health strategies—such as improved childhood nutrition, vaccination programs, and environmental regulation—offers a critical opportunity for cancer prevention. A shift toward early-life interventions is essential to reduce the long-term global cancer burden and advance equitable health outcomes.

Introduction. Kyrgyzstan, among other Central Asian countries, is one of the highly endemic regions for hepatitis A. An important tool for assessing the true burden of these infections on the population and the success of ongoing prevention programs is to study the prevalence of markers of past and current hepatitis A in all age groups of the population, as well as the intensity of population immunity to this virus in regions with different morbidity. Aim. To study the hepatitis A virus (HAV) seroprevalence among residents of the Kyrgyzstan regions. Materials and methods. Blood serum samples from conditionally healthy individuals (n = 2297) who sought medical attention at medical institutions in Bishkek, Batken, Chüy, Jalal-Abad, Issyk-Kul, Osh, Talas and Naryn regions. IgM and IgG antibodies to hepatitis A virus (anti-HAV IgM, anti-HAV IgG) were determined using the «Vectohep A-IgM» and «Vectohep A-IgG» (Vector-Best) enzyme immunoassay kits. Statistical processing of the results was carried out using Excel and Medcalc programs. Results. 80.3% of the studied samples contained HAV serologic markers, of which 80.3% contained anti-HAV IgG antibodies and 4.7% contained anti-HAV IgM antibodies. All IgM-positive samples contained specific IgG antibodies. Such samples were identified with the same frequency among women and men. The highest seropositivity rates were observed in the age groups 30–39, 40–49, and 50–59 years. The number of individuals with anti-HAV IgG antibodies in their blood serum increased with their age. An analysis of the immunostructure of the examined individuals by the level of anti-HAV IgG in serum showed relatively stable ratios of low, medium and high levels of antibodies in groups older than 30 years. The most frequently anti-HAV IgM and IgG antibodies were detected in samples from residents of Bishkek. Anti-HAV IgG antibodies were detected in samples from all surveyed regions of Kyrgyzstan, while anti-HAV IgM antibodies were identified in samples from Chüy, Issyk-Kul and Osh regions, as well as Bishkek. Conclusion. Hepatitis A remains widespread in Kyrgyzstan. The determination of HAV seromarkers in the algorithms of complex hepatitis diagnostics and seroepidemiological studies remains relevant. A decrease in the level of population immunity to HAV in younger age group indicates the country's transition from high to medium endemicity, which suggests an increase in the number of clinically pronounced cases in the future in the absence of a hepatitis A vaccination program for children.

HighlightsPublic health relevance—How does this work relate to a public health issue?The World Health Organization (WHO) estimates that every year 1 billion people contract the flu, of which 3–5 million have serious symptoms and the number of deaths from respiratory diseases related to influenza infection is between 290,000 and 650,000.In Spain, from the 2023–2024 season, the influenza vaccine has become part of the routine vaccination program for children from 6 to 59 months.Public health significance—Why is this work of significance to public health?This work assesses the coverage and the adherence of influenza vaccination in children after the introduction of the influenza vaccine into the routine vaccination program in Spain for children under 5 years of age.It also attempts to identify the risk factors associated with influenza vaccination in all age groups (under 5 years and from 5 to 14 years with chronic pathologies).Public health implications—What are the key implications or messages for practitioners, policy makers and/or researchers in public health?Both the coverage and the adherence to influenza vaccination in children are very low, despite the introduction of a routine influenza vaccination program in children from 6 to 59 months.Factors associated with influenza vaccination in children aged 6–59 months included immigrant origin, urban residence, the presence of multiple risk factors, and specific underlying chronic conditions.Vaccination is the primary method of preventing influenza. During the 2023–24 season, the influenza vaccination for all children between 6 and 59 months was introduced for the first time in Spain. To assess the coverage and adherence of influenza vaccination in childhood during the first two seasons of a vaccination program, as well as to identify the factors associated with influenza vaccination in all children under 5 years of age and those from 5 to 14 years of age with risk factors. Retrospective observational study. All children eligible for the flu vaccine in Central Catalonia during the 2023–24 and 2024–25 seasons were included. A total of 39,937 children were studied. Of these, 79.1% had not been vaccinated for influenza in either of the seasons studied. Influenza vaccination coverage in childhood was 18.1% and 19.3% in the 2023–24 and 2024–25 seasons, respectively. In the 6- to 59-month age range, coverage was 19.1% and 28.9% in the 2023–24 and 2024–25 seasons, respectively. The adherence to vaccination in both seasons was 17%. Some variables (being a non-native person, living in an urban area, having more than one risk factor, or certain underlying conditions) were associated with the influenza vaccination. Coverage and adherence to influenza vaccination in childhood are very low, despite the implementation of a routine influenza vaccination program.

People in prison are at increased risk of bloodborne virus (BBV) infections, including hepatitis B virus (HBV). This study evaluated HBV prevalence, and history of testing, treatment and vaccination among people in Australian prisons. The AusHep study was a bio-behavioral survey (2022-23) among randomly selected individuals from 23 representative Australian prisons. Participants were tested for BBVs, including HBV surface antigen (HBsAg). Demographics, risk behaviors, and previous HBV testing, treatment and vaccination data were collected through interview-based surveys. Overall, 1599 participants were enrolled (89 % male; median age 35 years, 49 % First Nations people). National HBsAg prevalence (weighted estimate) was 0.52 % (95 %CI: 0.25-1.10), overall, including 1.03 % (95 %CI: 0.51-2.08) among First Nations people, 2.26 % (95 %CI: 0.44-10.75) among non-First Nations people born in moderate/high prevalence countries, and 0.02 % (95 %CI: 0.00-10.75) among non-First Nations people born in low prevalence countries (including Australia). The odds of HBV infection (i.e., HBsAg-positive) was greater among First Nations people [adjusted OR (aOR): 4.68, 95 %CI: 1.35-16.24], and lower among people with a history of injecting drug use (aOR: 0.15, 95 %CI: 0.04-0.54). Among all participants, 48.5 % (95 %CI: 45.3-51.7) reported a history of HBV testing (42.0 % in prison), with testing most likely among people with a history of injecting drugs (aOR: 3.82, 95 %CI: 2.80-5.23). Among 15 HBsAg-positive participants, four reported receiving HBV treatment. Among 1584 HBsAg-negative participants, 41.9 % (95 %CI: 38.8-45.1) reported receiving HBV vaccination (24.2 % received ≥3 doses, 28.9 % received their latest dose in prison). HBsAg prevalence was low overall, but disproportionately higher among First Nations people and people born overseas. Lower likelihood of HBV in people injecting drugs might be explained by higher chance of spontaneous clearance in adulthood or high-coverage HBV vaccination programs for children and adolescents, and subsequent immunity in many people by the time they start injecting drugs. Prison-based HBV testing uptake and vaccination coverage were sub-optimal. Targeted, jurisdiction- and population-specific strategies are needed to improve prison-based HBV care.

Respiratory syncytial virus (RSV), the leading cause of hospitalization among U.S. infants, results in 50,000-80,000 associated hospitalizations and 100-300 deaths among children aged <5 years each year (1). In 2023, the Advisory Committee on Immunization Practices (ACIP) recommended two options for preventing severe RSV in infants: maternal RSV vaccination during pregnancy (2) or administration of nirsevimab, a long-acting monoclonal antibody to infants (1). Nirsevimab is recommended for infants aged <8 months during their first RSV season (October-March in most of the United States); ideally, it should be administered during the birth hospitalization or within the first week of life. In September 2023, ACIP passed a resolution to add nirsevimab to the Vaccines for Children (VFC) Program, a public-private partnership that provides CDC-purchased vaccines to VFC-eligible children (those who are uninsured or underinsured, insured through Medicaid, or who are American Indian or Alaska Native) at no cost. Approximately one half (52.2%) of U.S. children aged 19-35 months are VFC-eligible, and among those, 93.4% are insured by Medicaid (3). Medicaid-insured infants have a higher incidence of severe RSV infection than do privately insured infants (4). Providers enrolled in the VFC program are able to administer nirsevimab at no cost to eligible children. Enrollment of birthing hospitals in VFC thus has the potential to expand infant immunization against RSV. This report describes enrollment of U.S. birthing hospitals (those with more than one birth during the previous year or at least one registered maternity bed) in the VFC program since the introduction of nirsevimab.

While childhood vaccination programmes provide outstanding contributions to improving health, they can also pose challenges through the interactions between parents and healthcare. This paper focuses on the ethical dimensions of interactions between healthcare professionals and parents. Since the knowledge that professionals possess creates an asymmetrical relationship with parents, it can be helpful to analyse the situation from a power perspective. An example of ethical problem-solving using a simple model for discussing ethically difficult situations is demonstrated.

High childhood vaccination coverage is critical for safeguarding public health. Sustaining high coverage requires effective infrastructure and delivery systems, as well as attention to individual decision-making, which is shaped by social, psychological and contextual factors. To optimize uptake, vaccination programmes must account for these influences and their interactions. To advance understanding on parental childhood vaccination readiness and to inform strategies for maintaining high uptake, we conducted a survey in August 2023 among 2077 parents in Norway whose children (aged 0-5 or 8-16years) were age-eligible for the national Childhood Immunization Programme (CIP). We examined factors associated with childhood vaccination readiness among parents using the validated 7C model, which assesses seven psychological antecedents of vaccination and provides an overall readiness score. Overall parental childhood vaccination readiness was high. However, lower readiness was significantly associated with negative experiences with vaccination services, not being sufficiently informed about vaccines at the health clinic, finding vaccination less accessible, and sociodemographic factors. Moreover, reliance on official public health information sources (e.g., child health clinics, government websites) for vaccination decision-making was positively associated with readiness, while reliance on social media, YouTube, or religious institutions corresponded with lower readiness. Overall readiness was also associated with vaccination behaviors: parents who had previously declined or postponed childhood vaccinations had substantially lower vaccination readiness scores. These findings show that experiential, informational and sociodemographic factors are associated with parents' childhood vaccination readiness. Efforts to improve communication and trust, including in parent-provider encounters, may be crucial to maintaining high and equitable coverage in childhood vaccination programmes.

Abstract Background Invasive pneumococcal disease (IPD) is a major cause of communicable disease burden in Europe and globally. Pneumococcal vaccines cover common IPD serotypes; vaccine failures should be monitored to follow-up National Vaccination Programmes (NVPs). In Finland, the 10-valent pneumococcal conjugate vaccine (PCV10) was included in the NVP with a 2 + 1 schedule in 09/2010 for children born since 06/2010. We performed a retrospective register-based study of IPD among PCV10 eligible children to identify vaccine failures and breakthrough cases. Methods We retrieved notified IPD cases during 09/2010-02/2025 in children born after 01/06/2010 from the National Infectious Diseases Register, and their PCV10 vaccination status from the National Vaccination Register. Vaccine failure was defined as PCV10 serotype IPD in a fully vaccinated child (3 doses) and vaccine breakthrough infection as PCV10 serotype IPD in a child who had received 1-2 doses of PCV10 ≥14 days before a positive laboratory test. Results Among 441 IPD cases, serotypes were available for 428 (97%); of these, 361 (84%) were partially (n = 92) or fully (n = 269) vaccinated prior to diagnosis. Among those, the most common serotypes were non-PCV10 serotypes 19A (n = 183), 3 (n = 55), 6C (n = 17), 22F (n = 16), and 23B (n = 14). We identified nine vaccine failures and six vaccine breakthrough cases, i.e. 3.3% and 6.5% of the fully and partially vaccinated IPD cases, respectively. Vaccine failures were serotypes 6B (n = 4), 19F (n = 2), 23F (n = 2), and 14 (n = 1). Vaccine breakthrough cases were serotypes 19F (n = 2), 23F (n = 2), 7F (n = 1), and 1 (n = 1). Most vaccine failure (7/9) and breakthrough (4/6) cases were female, all were &amp;lt;5 years of age. 5/6 breakthrough cases had received one PCV10 dose. Conclusions Vaccine failures and breakthroughs were rare, indicating success of the NVP. Higher-valency vaccines cover the most common IPD serotypes in partially and fully vaccinated children, which has informed an upcoming NVP change to PCV13. Key messages • Vaccine failures and breakthroughs were rare after more than 14 years of 10-valent pneumococcal conjugate vaccine use in the national vaccination programme for children in Finland. • Higher-valency conjugate vaccines cover the most common IPD serotypes in partially and fully vaccinated children. This has informed an upcoming national vaccination programme change.

Pertussis, or whooping cough, remains a significant public health issue in Iran, despite high vaccination coverage. The incidence of pertussis has increased over the past two decades, attributed primarily to the waning of vaccine-induced immunity, particularly in adolescents and adults, who may act as reservoirs and transmit the infection to infants. Additional contributing factors include increased population density in closed communities,, incomplete primary immunization in infants, the presence of unvaccinated or partially vaccinated Afghan immigrants, and suboptimal booster coverage in older populations, particularly due to the absence of a national booster vaccination program for children beyond 72 months of age. In the present study, we reviewed and analyzed epidemiological studies on pertussis seroprevalence and diagnostic confirmation rates in Iran. Screening published reports from PubMed, Scopus, Web of Science, and Google Scholar revealed that the pooled seroprevalence of pertussis-specific IgG was 47.79% among vaccinated healthy Iranians, reflecting the overall level of antibody presence in this population. Comparing diagnostic methods, PCR-based diagnosis had a significantly higher confirmation rate (15.94%) compared to culture (3.02%) for detection of pertussis among suspected Iranian cases, emphasizing the need for improved diagnostic protocols. Although vaccination coverage has exceeded 95% since 1988, the persistence of pertussis suggests that current immunization strategies may be inadequate. Studies show that circulating Bordetella pertussis strains exhibit genetic variations that could contribute to vaccine escape. However, the body of evidence suggests that loss of acquired immunity over time palys the main role in pertussis resurgence. Whole-cell pertussis vaccines remain the primary immunization strategy in Iran. Considering the lower rate of adverse effects, acellular vaccines have been suggested to be used as booster doses, especially for adolescents and pregnant women. As a result, in order to prevent pertussis in newborn/young infants, many health authorities now recommend booster doses for adolescents, young adults, and pregnant women. In conclusion, pertussis continues to pose a public health challenge in Iran. Addressing this issue requires improved diagnostic techniques, enhanced surveillance, and consideration of updated vaccination strategies. Future research should focus on genomic surveillance, antibiotic resistance, and the long-term efficacy of booster immunizations to reduce pertussis transmission and protect vulnerable populations.

Hepatitis B virus (HBV) infection is a significant public health concern, particularly in low-income countries. This study investigates the prevalence and associated risk factors of HBV in Alamata district of Tigray region, northern Ethiopia, where the HBV vaccine was introduced in the childhood vaccination programme in 2007. A community-based, cross-sectional study was conducted from December 2019 to June 2020. Data were collected using structured questionnaires and hepatitis B surface antigen (HBsAg) was measured using a rapid diagnostic test. Logistic regression analyses were used to determine the associations between socio-demographic, behavioural and health-related variables and HBV infection. A total of 1853 individuals (54.2% females) were included in this study. The age ranged from 5 to 88 years, and the largest age group was from 5 to 14 years (32.0%). The overall HBV prevalence was 5.3% (95% confidence interval (CI) 4.3-6.3) with significant variability between age groups: 5-14 years 3.7%, 15-24 years 6.8%, 25-34 years 10.1%, 35-44 years 4.4%, 45-54 years 3.9% and 55 years and above 3.4%. Being in the 25-34 years age group (adjusted odds ratio (AOR) 4.1, 95% CI: 1.1-16.2, P= 0.042), reporting multiple sexual partners (AOR 4.0, 95% CI: 1.02-15.4, P= 0.047) and family history of hepatitis B (AOR 3.1, 95% CI: 1.2-8.2, P= 0.024) were independently associated with HBV infection. The prevalence of HBV infection was high in this region, underscoring the necessity for targeted public health strategies aimed at reducing transmission rates. Of note, the HBV prevalence was significantly lower among children born after the introduction of the HBV vaccine.