Reference:
Kerr, S., Bedston, S., Bradley, D. T., Joy, M., Lowthian, E., Mulholland, R. M., Akbari, A. F. D., Hobbs, R., Katikireddi, S. V., de Lusignan, S., Rudan, I., Torabi, F., Tsang, R. S.
M., Lyons, R. A., Robertson, C., & Sheikh, A. (2023). COVID-19 Waning of first- and second-dose ChAdOx1 and BNT162b2 vaccinations: A pooled target trial study of 12.9 million individuals in England, Northern Ireland, Scotland and Wales. International Journal of Epidemiology, 52(1), 22–31. https://doi.org/10.1093/ije/dyac199
Summary:
This study investigates the waning effectiveness of COVID-19 vaccinations (ChAdOx1 and BNT162b2) across the UK, analysing data from 12.9 million individuals. Findings reveal significant decreases in vaccine effectiveness (VE) and relative vaccine effectiveness (rVE) for ChAdOx1 within 60-80 days post-vaccination, with some doses showing negative effectiveness. In contrast, the second dose of BNT162b2 maintained a positive rVE for the entire follow-up period. The research underlines the importance of monitoring vaccine effectiveness over time to inform public health policy on booster doses.