July 31 (UPI) -- Front-line healthcare workers in the United States and Britain were more than three times as likely to report a positive COVID-19 test during the first few weeks of the pandemic, an analysis published Friday by The Lancet Public Health found.
The findings are based on self-reported data from nearly 100,000 American and British clinicians using the COVID Symptom Study smartphone app, recorded between March 24 and April 23, according to the researchers.
Preliminary results also suggest that healthcare workers' ethnic background and clinical setting, as well as the availability of personal protective equipment, or PPE, were important factors in their likelihood of testing positive for COVID-19, the researchers said.
"Previous reports from public health authorities suggest that around 10% to 20% of COVID-19 infections occur among health workers," co-author Dr. Andrew Chan said in a statement. "Many countries, including the U.S., continue to face vexing shortages of PPE."
"Our results underscore the importance of providing adequate access to PPE and also suggest that systemic racism associated with inequalities to access to PPE likely contribute to the disproportionate risk of infection among minority front-line healthcare workers," said Chan, director of cancer epidemiology at Massachusetts General Hospital.
The prevalence of COVID-19 was 2,747 per 100,000 app users among front-line care workers, compared with 242 per 100,000 app users from the general public, according to the researchers.
Gloves, gowns and face masks are recommended for those caring for COVID-19 patients, but surging demand and supply chain disruptions resulted in global shortages, the researchers said.
Some areas have attempted to conserve PPE by reusing items or using them longer, but data on the safety of such practices is scarce, they said.
For their research, Chan and his colleagues asked COVID Symptom Study smartphone app users to provide background information about themselves, whether they work in healthcare, if they have direct contact with patients and if enough PPE was available when needed.
More than 2.6 million people participated in the COVID Symptom Study, including just under 200,000 in the United States, the researchers said.
Of these, just under 100,000 identified themselves as front-line healthcare workers and just over 5,500 reported testing positive for COVID-19, the analysis found.
Front-line healthcare workers who reported having inadequate PPE were 1.3 times more likely to have COVID-19 than those with adequate PPE, the researchers found.
Healthcare workers who reused PPE were almost 1.5 times more likely to have COVID-19, and healthcare workers caring for patients with COVID-19 without adequate PPE were almost six times more likely to test positive, the researchers said.
Even with adequate PPE, the risk of getting COVID-19 was almost 2.4 times greater for those caring for suspected COVID-19 patients -- and around five times greater for those caring for people with confirmed COVID-19 -- compared with those who were not exposed to COVID-19 patients, the researchers said.
After accounting for pre-existing medical conditions, healthcare workers from Black, Asian and minority ethnic backgrounds were almost five times more likely to report a positive COVID-19 result than somebody from the public, the researchers said.
White healthcare workers were around 3.5 times more likely to have COVID-19 than the public, they said.
The prevalence of COVID-19 among U.S. healthcare workers -- 461 per 100,000 app users -- was almost twice that of their British counterparts, at 227 per 100,000 app users, the researchers said.
"Our findings highlight structural inequities in COVID risk," study co-author Erica Warner said in a statement.
"Ensuring access to, and appropriate use of, high-quality PPE across care settings would help mitigate these disparities," said Warner, an assistant professor of medicine at Harvard Medical School.