March 15, 2021

An Observational Cohort Study on the Incidence of SARS-CoV-2 Infection and B.1.1.7 Variant Infection in Healthcare Workers by Antibody and Vaccination Status

Category: Article Summary

Topic: Vaccines and Immunity

Keywords (Tags): immunity

• [Pre-print, not peer-reviewed] A longitudinal cohort study of healthcare workers (HCWs) in England showed that both natural infection and vaccination (two doses of Pfizer/BioNTech or Oxford/AstraZeneca vaccine) provided more than 85% protection against symptomatic and asymptomatic SARS-CoV-2 infection, including with the B.1.1.7 variant. No HCWs who had received both doses had symptomatic infection, and incidence was 98% lower among seropositive HCWs (aIRR = 0.02). Two vaccine doses or seropositivity reduced the incidence of any PCR-positive result with or without symptoms by 90% and 85%, respectively. Single-dose vaccination was slightly less effective and reduced the incidence of symptomatic infection by 67% and any PCR-positive result by 64%. 

Lumley et al. (Mar 12, 2021). An Observational Cohort Study on the Incidence of SARS-CoV-2 Infection and B.1.1.7 Variant Infection in Healthcare Workers by Antibody and Vaccination Status. Pre-print downloaded Mar 15 from https://doi.org/10.1101/2021.03.09.21253218