PORTLAND, Ore. — A months-long COVID-19 antibody study by Providence researchers revealed a low percentage of positive tests among more than 10,000 health care workers tested during the early months of the pandemic.
Researchers said the low rate was due, in part, to social distancing and the use of personal protective equipment (PPE) in hospitals.
Providence released results of the study on Wednesday. Back in April and May, a total of 10,019 Providence Oregon caregivers from eight different hospitals received blood tests that can detect antibodies to SARS-CoV-2, the virus that causes COVID-19.
Researchers found 253 people, 2.53% of participants, tested positive for antibodies. Those people were exposed to COVID-19, but they did not necessarily have the virus, researchers said.
"Health care workers were and are an important group to study because we need to know how common exposure is with the people who serve in our medical centers and who otherwise don’t have signs or symptoms of infection," said Carlo Bifulco, medical director of Providence St. Joseph Health Cancer Genomics Laboratory.
Testing involved blood draws every 14 days over a four-week window during April and May, the peak early period of the COVID-19 pandemic in Oregon.
Researchers said the study gives them confidence that PPE is effective as limiting the spread of COVID-19 in hospitals.
The voluntary study was partially funded by donors. Plans are underway to expand the Providence study to health care workers in other states.