The initial impact of a national BNT162b2 mRNA COVID-19 vaccine rollout

Zaqout, Ahmed; Daghfal, Joanne; Alaqad, Israa; Hussein, Saleh A.N.; Aldushain, Abdullah; Almaslamani, Muna A.; Abukhattab, Mohammed; Omrani, Ali S.

Objective We herein report the initial impact of a national BNT162b2 rollout on SARS-CoV-2 infections in Qatar. Methods We included all individuals who by 16 March 2021 had completed ≥14 days of follow up after the receipt of BNT162b2. We calculated incidence rates (IR) and their 95% confidence intervals (CI), during days 1–7, 8–14, 15–21, 22–28, and >28 days post-vaccination. Poisson regression was used to calculate incidence rate ratios (IRR) relative to the first 7-day post-vaccination period. Results We included 199,219 individuals with 6,521,124 person-days of follow up. SARS-CoV-2 infection was confirmed in 1,877 (0.9%), of which 489 (26.1%) were asymptomatic and 123 (6.6%) required oxygen support. The median time from first vaccination to SARS-CoV-2 confirmation was 11.9 days (IQR 7.7–18.2). Compared with the first 7-day post-vaccination period, SARS-CoV-2 infections were lower by 65.8–84.7% during days 15–21, days 22–28, and >28 days (P < 0.001 for each). For severe COVID-19, the incidence rates were 75.7–93.3% lower (P < 0.001 for each) during the corresponding time periods. Conclusion Our results are consistent with an early protective effect of BNT162b2 against all degrees of SARS-CoV-2 severity.