May 17, 2021

Interim Estimates of Vaccine Effectiveness of Pfizer-BioNTech and Moderna COVID-19 Vaccines Among Health Care Personnel — 33 U.S. Sites, January–March 2021

Category: Article Summary

Topic: Vaccines and Immunity

Keywords (Tags): vaccine

• Among US healthcare personnel, one dose of either the Pfizer-BioNTech or Moderna vaccines was 82% effective against symptomatic COVID-19, and 2 doses were 94% effective. Interim results from a test-negative case-control study conducted in 25 states and enrolling 623 case-patients and 1,220 controls as of March 18, 2021 indicate that vaccine effectiveness is similar to vaccine efficacy reported in clinical trials. The effectiveness of a single dose was measured during the interval from 14 days after the first dose through 6 days after the second dose.

Pilishvili et al. (May 14, 2021). Interim Estimates of Vaccine Effectiveness of Pfizer-BioNTech and Moderna COVID-19 Vaccines Among Health Care Personnel — 33 U.S. Sites, January–March 2021. MMWR. Morbidity and Mortality Weekly Report. https://doi.org/10.15585/mmwr.mm7020e2