Forty percent of healthcare workers with COVID-19 were not showing symptoms when they were diagnosed, according to a new meta-analysis published in the American Journal of Epidemiology.
Researchers examined 97 studies published in 2020, including 230,398 healthcare workers across 24 countries.
The analysis found the estimated prevalence of infection was 11 percent among healthcare workers using polymerase chain reaction testing, and 7 percent of healthcare workers were positive by antibody tests.
Nearly half (48 percent) of healthcare workers testing positive for COVID-19 were nurses, and 25 percent were physicians, according to the analysis. Twenty-three percent were other healthcare workers.
Forty-three percent of COVID-19 positive medical personnel were working in hospitalization/non-emergency wards during the screening, the analysis found. Twenty-four percent of them were working in the operating room, 16 percent were working in the emergency room and 9 percent were working in the intensive care unit. Twenty-nine percent reported "other" locations.
"Loss of taste and smell (anosmia), fever and muscle pain were identified as the only symptoms significantly associated with … positivity among" workers, co-author Taulant Muka, MD, PhD, from the Institute of Social and Preventive Medicine, University of Bern, Switzerland, said in a news release.
Additionally, among healthcare workers positive by polymerase chain reaction testing, 40 percent were asymptomatic at the time of screening. Five percent of infected healthcare workers developed severe clinical complications, and 0.5 percent died, the analysis found.
Dr. Muka said: "Healthcare workers suffer a significant burden from COVID-19. A significant proportion of healthcare workers are positive for COVID-19 while asymptomatic, which might lead to the silent transmission of the disease within hospitals and in the community. The symptoms associated with COVID-19 in HCW could be used as an indicator for screening in settings with limited testing capacities."
Co-author Professor Oscar Franco, MD, PhD, from the Institute of Social and Preventive Medicine, University of Bern, Switzerland, concluded in a news release: "Because we might miss a large proportion of COVID-19 cases if screening targets only symptomatic HCW, universal screening for all exposed HCW regardless of symptoms should be the standard strategy. While more research is needed to understand specific interventions that can help reducing SARS-CoV-2 infection among healthcare personnel, it is clear that providing healthcare workers with adequate personal protective equipment and training is essential."