Covid-19 Breakthrough Infections in Vaccinated Health Care Workers

To the Editor: In their article on breakthrough infections among health care workers who had been fully vaccinated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, Bergwerk and colleagues (published online on July 28)(1) report that among 1497 such workers for whom polymerase-chain-reaction (PCR) data were available, 39 breakthrough infections were documented at their facility. There were no cases of secondary transmission among 31 of the workers with breakthrough cases who had available data regarding household transmission. Since March 2021, we have identified 4 breakthrough infections among 8678 fully vaccinated health care workers at Asan Medical Center. All 4 . . .

Automated summary

A study found that breakthrough infections among fully vaccinated healthcare workers are limited, with no evidence of secondary transmission in most cases. Despite some breakthrough infections, the proportion of such cases is relatively low among fully vaccinated healthcare workers.