SARS-CoV-2, COVID-19 rates decreased after one vaccine dose | Medical Xpress


(HealthDay)—Substantial reductions in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and symptomatic COVID-19 have been reported following administration of one dose of the BNT162b2 COVID-19 vaccine, according to a research letter published online Feb. 18 in The Lancet.

Sharon Amit, from The Chaim Sheba Medical Center in Ramat-Gan, Israel, and colleagues assessed vaccine-associated rate reductions in SARS-CoV-2 infection and COVID-19 rates in a retrospective cohort involving 9,109 vaccine-eligible health care workers (HCWs).

Overall, 7,214 (79 percent) and 6,037 (66 percent) had received their first and second doses, respectively, by Jan. 24, 2021. The researchers identified 170 SARS-CoV-2 infections between Dec. 19, 2020, and Jan. 24, 2021, for which 99 HCWs reported symptoms and were designated COVID-19 cases. Of the HCWs who became infected, 52 percent were unvaccinated and 46 and 2 percent tested positive after the first and second dose, respectively. The SARS-CoV-2 infection rate was 7.4 per 10,000 person-days among unvaccinated HCWs compared with 5.5 and 3.0 per 10,000 person-days on days 1 to 14 and 15 to 28 after the first vaccine dose, respectively, with adjusted rate reductions of 30 and 75 percent, respectively. The symptomatic COVID-19 rate was 5.0 per 10,000 person-days in unvaccinated HCWs compared with 2.8 and 1.2 per 10,000 person-days on days 1 to 14 and 15 to 28 after the first dose, respectively; adjusted rate reductions were 47 and 85 percent, respectively.

“Early reductions of COVID-19 rates provide support of delaying the second dose in countries facing vaccine shortages and scarce resources, so as to allow higher population coverage with a single dose,” the authors write.

Follow the latest news on the coronavirus (COVID-19) outbreak

More information:
Abstract/Full Text

Copyright © 2020 HealthDay. All rights reserved.

SARS-CoV-2, COVID-19 rates decreased after one vaccine dose (2021, February 22)
retrieved 22 February 2021

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.