Association Between Primary COVID-19 Vaccine Platform and Booster Uptake Among Incarcerated People: A Retrospective Cohort Study

Le résumé fourni par la source

Introduction : COVID-19 booster doses remain critical for maintaining protection against SARS-CoV-2, particularly in high-risk congregate settings such as correctional facilities. However, factors influencing booster uptake in these settings remain poorly understood. This study assessed whether primary COVID-19 vaccine platform (viral vector or mRNA) was associated with booster receipt among incarcerated individuals in Connecticut. Methods : A retrospective cohort study of individuals who completed a primary COVID-19 vaccine series and, while incarcerated, became booster eligible was conducted using Connecticut Department of Correction records from July 1, 2021, to May 31, 2023. The association between primary series platform and time to booster receipt was modeled using adjusted Cox proportional hazards models and the mediational g-formula was used to examine whether breakthrough SARS-CoV-2 infection mediated the association between vaccine platform and booster receipt. Results Among the 6,138 included individuals (median age at eligibility: 40 years), 719 received Janssen for their primary series, 4,897 received Moderna, and 522 received Pfizer. Overall, 3,714 individuals (60.5%) received a booster: 39.1% of Janssen recipients, 65.4% of Moderna recipients, and 44.4% of Pfizer recipients. Compared to Janssen recipients, the adjusted hazard of booster receipt was higher among mRNA (combined) recipients (aHR: 2.04; CI:1.67–2.48), as well as for Moderna recipients (aHR: 2.09; CI:1.72–2.56) and Pfizer recipients (aHR: 1.75; CI:1.39–2.21). The mediation analysis suggests that this association was not mediated by breakthrough infections (total indirect effect (HR): 1.01; CI: 0.98–1.04). Conclusion : Primary vaccine platform was strongly associated with booster uptake in this incarcerated population despite relatively uniform access to vaccination. These findings suggest that early vaccine experiences may shape subsequent vaccination behavior. As U.S. COVID-19 vaccination policy increasingly emphasizes shared clinical decision-making, the influence of early vaccine decisions on booster uptake may have important implications for sustaining vaccination coverage in high-risk populations.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.