The COVID-19 pandemic has caused a substantial global health burden, highlighting the need for post-authorization safety evaluation in real-world settings. BNT162b2 is a widely used mRNA COVID-19 vaccine, and, in addition to the original strain-based formulation, BA.1-, BA.4/5-, XBB.1.5-, and JN.1-adapted formulations were introduced sequentially. This study aimed to evaluate the real-world safety profile of the BNT162b2 product family using post-marketing surveillance data collected in Korea. Data collection was conducted from 50 sites. Solicited adverse events (AEs) were collected for 7 days, and unsolicited AEs for 28 days after vaccination. AEs occurring beyond Day 28 were also collected if reported during routine follow-up, without restriction on the collection period. Of 6,343 enrolled participants, 6,251 were included in the safety analysis set. Overall AEs were reported in 1,640 participants (26.2%) and adverse drug reactions (ADRs) in 1,610 participants (25.8%). Serious AEs occurred in 2 participants (<0.1%), and serious ADRs in 1 participant (<0.1%); no unexpected serious ADRs were identified. Solicited AEs were predominantly mild reactogenicity events, most commonly injection site pain, myalgia, fatigue, and headache. The overall safety profile of the BNT162b2 product family was generally manageable in this predominantly adult population, with very few serious ADRs and no unexpected serious ADRs identified. However, due to limited systematic capture of adverse events of special interest (AESIs) and underrepresentation of pediatric participants, AESI-related findings and pediatric safety conclusions should be interpreted with caution. These findings provide complementary real-world evidence regarding the safety of BNT162b2-adapted vaccines in Korea.
India aims to eliminate measles and rubella (MR) by 2026. Despite >90% vaccination coverage reported in NFHS-5 and NFHS-6, assessing population-level immunity gaps remains essential to guide strategies for protecting vulnerable groups. We leveraged biobanked samples from two community-based serosurveys conducted in urban Vellore in 2013 and 2022, representing periods 5 years before and after the nationwide MR vaccination campaign. Age- and sex-stratified participants were tested for measles- and rubella-specific IgG antibodies using ELISA. Seroprevalence estimates were compared across surveys, and generalized additive models (GAM) were used to assess age-specific seropositivity patterns. Effective reproduction numbers (Re) for measles and rubella were estimated using mixture modeling approaches. A total of 1,029 samples from 2013 and 718 samples from 2022 were analyzed. Measles seroprevalence increased from 33%, 41%, 47%, and 48% in the 1–5, 6–15, 16–40, and >40 years age groups in 2013 to 77%, 71%, 89%, and 96% respectively in 2022. Rubella seroprevalence increased from 32%, 67%, 76%, and 73% to 93%, 84%, 93%, and 98% across the same age groups. No significant sex-based differences were observed for either infection. The estimated Re declined from 7.4 to 3.6 for measles and from 1.8 to 0.8 for rubella following the MR campaign period. Population immunity improved by 2022, particularly for rubella. However, lower measles seroprevalence among children aged 1–15 years indicates persistent immunity gaps despite high vaccine coverage, highlighting the need for continued surveillance and targeted strategies to achieve measles–rubella elimination in India.
Vaccinology has expanded considerably in recent decades through new platforms, delivery technologies, regulatory science and applications beyond infectious diseases. Most of this growth has followed one direction, enlarging the range of products and targets included in vaccine science. This commentary argues that a second direction of expansion deserves explicit recognition: from the vaccine as a biomedical product to vaccination as a social practice. Alongside basic vaccinology, which asks whether a vaccine works, and programmatic vaccinology, which asks whether vaccination can be delivered, social vaccinology asks how vaccination interacts with society, including institutions, policies, public trust and public discourse. The idea has deep roots. The early formulations of the discipline by Bruce Dull in 1971 and by Jonas and Darrell Salk between 1977 and 1984 already included the technical, administrative and social aspects of vaccination programs, and the term social vaccinology was proposed in 2012. Recent experiences with HPV vaccination in Japan and with childhood immunization policy in the United States show how vaccination outcomes depend on this domain, and work on vaccine hesitancy and communication points in the same direction. Recognizing social vaccinology within the field would have implications for research agendas, the training of vaccinologists and scientific publishing.
In 2025, China adjusted national immunization schedule to administer a booster dose of acellular diphtheria-tetanus-pertussis combined vaccine (DTaP) to 6-year-old children, replacing the previously used diphtheria-tetanus combined vaccine (DT). Post-marketing safety surveillance of this newly implemented schedule is critical to evaluate the tolerability and safety of DTaP in this age group. To evaluate the epidemiological characteristics and safety of adverse events following immunization (AEFI) among 6-year-old children after administration of DTaP following the 2025 national immunization schedule adjustment in Hangzhou. To compare the incidence of AEFI between DTaP and DT. AEFI surveillance and vaccination data of 6-year-old children who received DTaP or DT from 2024 to 2025 in Hangzhou were collected. The total sample size was 239 480 doses of diphtheria-tetanus-containing vaccines. Descriptive statistics, chi-square test, and reporting odds ratio disproportionality analysis were used for statistical analysis. The overall reporting rate of AEFI following vaccination with diphtheria- and tetanus-containing vaccines among 6-year-old children in Hangzhou was 466.01 per 100,000 doses. The AEFI reporting rate for DTaP (833.58 per 100,000 doses) was significantly higher than that for DT (181.49 per 100,000 doses) (χ2 = 539.95, P < .05). AEFIs after DTaP vaccination were predominantly general reactions (99.31%), and no severe AEFI was reported. Disproportionality analysis detected positive signals only for local redness/swelling as a general reaction for both DTaP and DT. DTaP vaccination is safe and well-tolerated after the immunization schedule adjustment. Most AEFIs are mild general reactions including fever, redness, and induration, with reporting rates within the expected range and no obvious safety risks.
China has implemented universal hepatitis B vaccination in all neonates since 2002 and has enhanced prophylaxis against mother-to-child transmission of hepatitis B virus (HBV) by providing charge-free hepatitis B immunoglobulin in infants of HBV-infected mothers since 2011 and by recommending routine antiviral prophylaxis in HBV-infected mothers with high viral loads since 2020. We aimed to survey the seroprevalence of hepatitis B surface antigen (HBsAg) in children born from 2010 to 2024 in Jiangsu Province, based on convenience sampling in children who visited hospitals. We tested hepatitis B markers in 20,317 children aged 7.9 ± 4.1 years, with 11477 boys and 8840 girls, from 8 cities across Jiangsu during February 2023 to December 2025. Of them, 14 (0.069%, 95% CI: 0.038–0.116) were HBsAg positive. The positive rates of HBsAg in 0.5–<3, 3–<6, 6–<9, 9–<12, and 12–<15 years groups were 0% (0/2520), 0% (0/3858), 0.024% (1/4243), 0.136% (6/4401), and 0.132% (7/5295), respectively (P = .01489). The overall positive rate of antibody against HBsAg was 68.11% (12046/17686), with a decreasing trend over the ages (from 96.17% in 0.5–<3 year children to 48.41% in 12–<15 year children). In HBsAg-negative children, the positive rate of antibody against hepatitis B core antigen was 7.68% (1383/18007), increasing from 4.23% in 0.5–<3 year children to 7.84% in 12–<15 year children (Z = 5.0398, P < .0001). The present study showed that HBsAg prevalence among children in Jiangsu has substantially declined since the implementation of enhanced prevention of HBV perinatal infection.
