News Scan for Aug 16, 2022

Healthcare workers wearing respirators 40% less likely to contract COVIDA study of more than 2,900 healthcare workers (HCWs) shows that those who wore a respirator were more than 40% less likely to be infected with COVID-19 than those wearing a surgical mask.In the study, published yesterday in JAMA Network Open, researchers evaluated SARS-CoV-2 infection rates and cumulative COVID-19 patient exposures among 2,919 HCWs at seven healthcare networks in Switzerland from September 2020 to September 2021, before the Omicron variant became widespread.At the end of the study, the team asked participants whether they had worn FFP2 respirators (similar to N95 respirators in the United States) or surgical masks during contact with COVID-19 patients other than during aerosol-generating procedures.

To quantify cumulative patient exposures, the researchers multiplied the self-reported number of contacts with COVID-19 patients by average contact duration.Of the 2,919 HCWs, 749 (26%) tested positive for COVID-19.

Among participants with patient exposure, test positivity was 21% for those wearing a respirator, compared with 35% in those using surgical masks or a mix of masks (odds ratio [OR], 0.49).Risk factors for COVID-19 infection included an infected household member (OR, 7.79) and exposure to patients (OR, 1.20 per category of cumulative contact), while respirator use (OR, 0.56) and vaccination (OR, 0.55) were protective."SARS-CoV-2 positivity in HCWs was associated with cumulative COVID-19 patient exposure," the researchers wrote. "The odds of being SARS-CoV-2–positive were reduced by more than 40% in individuals using respirators irrespective of cumulative exposure, even after adjusting for multiple work- and nonwork-related