학술논문

Effectiveness of BNT162b2 BA.4/5 Bivalent mRNA Vaccine Against Symptomatic COVID-19 Among Immunocompetent Individuals Testing at a Large US Retail Pharmacy.
Document Type
Article
Source
Journal of Infectious Diseases. 3/15/2024, Vol. 229 Issue 3, p648-659. 12p.
Subject
Language
ISSN
0022-1899
Abstract
Background Data on the effectiveness of BA.4/5 bivalent vaccine stratified by age and prior infection are lacking. Methods This test-negative study used data from individuals ≥5 years of age testing for SARS-CoV-2 with symptoms (15 September 2022 to 31 January 2023) at a large national retail pharmacy chain. The exposure was receipt of 2–4 wild-type doses and a BNT162b2 BA.4/5 bivalent vaccine (>2 months since last wild-type dose). The outcome was a positive SARS-CoV-2 test. Absolute (vs unvaccinated) and relative (vs 2–4 wild-type doses) vaccine effectiveness (VE) were calculated as (1 − adjusted odds ratio from logistic regression) × 100. VE was stratified by age and self-reported prior infection. Results Overall, 307 885 SARS-CoV-2 tests were included (7916 aged 5–11, 16 329 aged 12–17, and 283 640 aged ≥18 years). SARS-CoV-2 positivity was 39%; 21% were unvaccinated, 70% received 2–4 wild-type doses with no bivalent vaccine, and 9% received a BNT162b2 BA.4/5 bivalent dose. At a median of 1–2 months after BNT162b2 BA.4/5 bivalent vaccination, depending on age group, absolute VE was 22%–60% and was significantly higher among those reporting prior infection (range, 55%–79%) than not (range, no protection to 50%). Relative VE was 31%–64%. Conclusions BNT162b2 BA.4/5 bivalent showed early additional protection against Omicron-related symptomatic COVID-19, with hybrid immunity offering greater protection. [ABSTRACT FROM AUTHOR]