Search PubMed⌕ Search
Home/Archive/PubMed

PubMed · 42661284

Stroke risk following BNT162b2 vaccination: a systematic review and meta-analysis of self-controlled case series studies.

Seol Jang·Sung-Inn Pyo·Eun Jin Kim·Woojoo Lee·Soon-Sun Kwon
View original source ↗Export metadata ↓

Abstract

INTRODUCTION: Whether BNT162b2 (Pfizer-BioNTech) vaccination increases stroke risk remains a public health concern. This is the first meta-analysis to synthesize self-controlled case series (SCCS)-derived stroke risk estimates specifically for BNT162b2 vaccination. METHODS: PubMed and Embase were searched from inception through 9 May 2026, following PRISMA 2020 guidelines. Eight eligible SCCS studies were pooled using a random-effects model with restricted maximum likelihood (REML) estimation and the Knapp-Hartung adjustment. RESULTS: Eight studies across six countries encompassing several million vaccinated individuals were included. The pooled incidence rate ratio (IRR) was 0.967 (95% CI 0.892-1.049; I2 = 69.2%), indicating no statistically significant increase in stroke risk. Subgroup analyses showed no evidence of effect modification across continent, risk-window length, dose category, SCCS variant, or age group. CONCLUSIONS: These findings provide no evidence of increased short-term stroke risk following BNT162b2 vaccination at the population level. The observed heterogeneity appeared to be partly driven by methodological differences rather than true biological variation in vaccine effect.

Explore related subjects

HumansBNT162 VaccineIncidenceStrokeVaccinationBNT162b2COVID-19 vaccinemeta-analysisself-controlled case seriesstrokevaccine safetyJournal ArticleMeta-AnalysisSystematic Review

Keep this discovery

BibTeXRIS

Seol Jang, Sung-Inn Pyo, Eun Jin Kim, Woojoo Lee, Soon-Sun Kwon. 2026-08-27. Stroke risk following BNT162b2 vaccination: a systematic review and meta-analysis of self-controlled case series studies.. https://doi.org/10.1080/14760584.2026.2720955

Cite the original work for its findings. Save a collection to share your selection of sources.

Discover connections

Journal Article; Meta-Analysis; Systematic Review resourceBNT162 Vaccine subjectBNT162b2 subjectCOVID-19 vaccine subjectHumans subjectIncidence subjectJournal Article subjectMeta-Analysis subjectSystematic reviews study

Connections use source metadata and explicit phrase matches, not verified experimental comparisons.

KEEP EXPLORING

Related citations

PubMed2026

A multi-center, open-labelled, randomized controlled extended phase III non-inferiority clinical trial to evaluate the immunogenicity and tolerability of poliomyelitis vaccine (Vero cells), inactivated, Sabin strains administered with or without routine infant vaccines.

BACKGROUND: Oral poliovirus vaccine (OPV) has been reported to cause vaccine-derived poliovirus and vaccine-associated paralytic poliomyelitis, and the limited global supply of conventional IPV has led many countries to rely on fractional-dose IPV regimens alongside OPV. The current study aims to assess the sIPV safety and immunogenicity when given concurrently with or in a staggered manner with routine immunization. METHODS: A multi-country, multi-center, open-label, randomized controlled, extended phase III non-inferiority clinical trial was conducted with 1442 healthy infants aged 6-8 weeks from Bangladesh and Pakistan enrolled and randomized into four groups, i.e., co-administration group 1 (group C1), co-administration group 2 (group C2), staggered administration group 1 (group S1) and staggered administration group 2 (group S2). Antibody levels were determined using the collected sera for immunogenicity evaluation. The difference in seroconversion rates between the coadministration group and the staggered administration group is compared using the Cochran-Mantel-Haenszel χ2 (CMH-χ2) test, stratified by study site. Non-inferiority is concluded if the lower bound of the 95% confidence interval (CI) for the rate difference (coadministration group minus staggered administration group) is greater than -10%. The trial was registered prior to patient enrollment at clinicaltrials.gov (NCT05850364), and the protocol and statistical analysis plan are available at https://clinicaltrials.gov/study/NCT05850364. The trial is closed to new participants. FINDINGS: The post-vaccination seroconversion rates for PV I were 90.3% (306/339) in group C1 and 87.0% (261/300) in group S1, for PV II, 91.7% (311/339) in group C1 and 91.3% (274/300) in group S1 and for PV III, 86.4% (293/339) in group C1 and 92.3% (277/300) in group S1. Among adverse reactions (ARs) reported within 7 days of vaccination, the incidence was similarly high in both the co-administration and staggered vaccination groups (92.8% vs. 95.5%). INTERPRETATION: Our results demonstrated favorable safety and immunogenicity of co-administration of sIPV with other routine infant vaccines according to a 3-dose primary immunization schedule.

Humans↗
PubMed2026

Adherence and efficacy of the 0 - 7 - 21-day versus the 0 - 1 - 6-month hepatitis B vaccination schedules among people who use drugs: a two-year randomized controlled trial.

BACKGROUND: To compare the adherence and efficacy between the 0&#x2009;-&#x2009;7&#x2009;-&#x2009;21-day and the 0&#x2009;-&#x2009;1&#x2009;-&#x2009;6-month hepatitis B virus (HBV) vaccination schedules among people who use drugs (PWUD) in China. RESEARCH DESIGN AND METHODS: A randomized controlled trial was conducted in 1261 HBV-susceptible PWUD from compulsory isolated detoxification centers (CIDCs) and methadone maintenance treatment (MMT) clinics in Xi'an. A 20&#x2009;&#xb5;g per-dose vaccine was used. HBV surface antibody (anti-HBs), surface antigen, and core antibody were tested at months 7, 15, and 22 after the first dose. RESULTS: Third-dose coverage was significantly higher in the 0&#x2009;-&#x2009;7&#x2009;-&#x2009;21-day group (74.40%) than in the 0&#x2009;-&#x2009;1&#x2009;-&#x2009;6-month group (51.58%, p&#x2009;<&#x2009;0.001), mainly driven by participants from CIDCs (77.75% vs. 45.69%). Anti-HBs positive rates at months 7, 15, and 22 among participants who completed all three doses were significantly higher for the 0&#x2009;-&#x2009;1&#x2009;-&#x2009;6-month schedule (90.71%, 76.82%, and 67.35%) than for the 0&#x2009;-&#x2009;7&#x2009;-&#x2009;21-day schedule (74.23%, 49.40%, and 40.95%; all p&#x2009;<&#x2009;0.001). HBV infection incidence was similar between schedules, but significantly different between vaccinees and non-vaccinees (p&#x2009;=&#x2009;0.018). CONCLUSIONS: The 0&#x2009;-&#x2009;7&#x2009;-&#x2009;21-day schedule substantially enhances three-dose completion in PWUD, but induces a notably weaker anti-HBs response and persistence. Schedules should be selected based on the management models for PWUD and their individual characteristics. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR1900022403).

Humans↗
PubMed2026

Vaccine preferences and their role for vaccine confidence and uptake: a meta-ethnography.

Vaccine confidence and uptake are influenced by individuals' preferences regarding vaccine composition, quality, or administration pathways. However, literature synthesizing available qualitative insights into individuals' vaccine preferences remains limited. We therefore conducted a meta-ethnographic systematic review of the qualitative literature on vaccine preferences to identify opportunities for enhancing vaccine confidence and uptake. We implemented a comprehensive search strategy and screened 5,528 studies across seven research databases published between 2001 and 2023. We identified and synthesized 97 qualitative articles to delineate factors influencing consumers' vaccine preferences. Our findings revealed four primary domains shaping individuals' vaccine preferences: Product, Place, Price, and Promotion. First, individuals' preferences for vaccines often hinge on perceived quality and safety of the product itself, which can, for example, be associated with vaccine brand or origin, especially in the case of novel vaccines. Second, people prioritize convenience in terms of vaccination sites and delivery methods (wanting vaccinations offered at their doorstep or in local peripheral clinics); evidence regarding preferred groups to administer the vaccines was mixed. Third, the price of vaccines and the secondary costs associated with vaccination played a role in uptake considerations. Finally, both the sources of information (such as healthcare workers, community volunteers, and religious authorities) and the methods of promoting vaccine information (including face-to-face consultations during clinic visits and the distribution of leaflets or banners), emerged as crucial factors shaping decision-making processes. Overall findings highlight the importance of addressing multifaceted preferences to enhance vaccine confidence and uptake. By understanding individuals' vaccine preferences, strategic recommendations can be developed to optimize vaccination programs and ensure acceptability and utilization.

Humans↗