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Abstract
Background: Following emergency use authorization of the Pfizer/BioNTech mRNA SARS-CoV-2 vaccine, BNT162b2, the Ministry of Health (MoH) launched a campaign to immunize all Israelis aged ≥ 16 years (6∙4 million).
Methods: Using national public health surveillance data from Jan 24, 2021–Mar 6, 2021, vaccine coverage and COVID-19 incidence were monitored and vaccine effectiveness (VE) was estimated, adjusted for age, sex, and week. Prevalence of SARS-CoV-2 variant B.1.1.7 was determined using polymerase chain reaction S gene target failure of selected specimens.
Findings: Through Mar 6, 2021, 51∙5% of persons aged ≥ 16 years received two doses of BNT162b2. During the observation period, SARS-CoV-2 B.1.1.7 prevalence was 93∙9%. Estimates of VE at ≥ 7 days after the second dose were: 94∙1% (95% CI 93∙4–94∙7) against SARS-CoV-2 infection, 90∙4% (95% CI 89∙1–91∙5) against asymptomatic SARS-CoV-2 infection, 96∙3% (95% CI 95∙9–96∙7) against symptomatic COVID-19 cases, 96∙0% (95% CI 95∙2 – 96∙6) against hospitalizations, 96∙2% (95% CI 95∙5–96∙8) against severe and critical hospitalizations, and 93∙3% (95% CI 91∙5–94∙8) against deaths. Estimates of VE were even higher at ≥ 14 days after the second dose of BNT162b2. In all age groups, as vaccine coverage increased, the incidence of SARS-CoV-2 outcomes declined markedly among the vaccinated.
Interpretation: Two doses of BNT162b2 were highly effective in preventing SARS-CoV-2 infections and COVID-19 cases, hospitalizations, severe and critical hospitalizations, and deaths in a large, nationwide observational study conducted when B.1.1.7 was the dominant SARS-CoV-2 strain. This study provides the first demonstration of the effectiveness of two doses of BNT162b2 against death and is also the first to show marked nationwide declines in incidence of SARS-CoV-2 infections corresponding with increasing vaccine coverage. The high VE in a real-world setting, including apparent effectiveness against asymptomatic infections, offers hope that COVID-19 vaccination will eventually control the pandemic.
Funding: Israel MoH and Pfizer.
Conflict of Interest: Frederick Angulo, John McLaughlin, Farid Khan, Gabriel Mircus, Kaijie Pan, Jo Southern, David Swerdlow, and Luis Jodar are employees of Pfizer and hold stock and stock options. All other authors report no conflicts.
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