Face Shields Reduced Percentage of Health Workers Infected With Covid-19 From 19% to Zero
A new Covid-19 study — published in the medical journal Jama Network — reports on the number of health workers who got infected before and after they included face shields as part of their personal protective equipment.
By Kam Kompani,
August 19, 2020
Among a group of 62 health workers, face shields reduced the percentage of infected personnel from 19% to zero.
All 62 workers were responsible for visiting households of Covid-19-infected individuals to discuss the principles of quarantining, mask use, social distancing, hand washing and Covid-19 symptoms with the other residents.
The workers were housed in separate hostel rooms throughout the duration of the study. They did not visit their homes or public places, and communicated with each other by phone. Each worker travelled in a small van with a steel partition between the driver and the back cabin. Their personal protective equipment included alcohol-based handrub, three-layered surgical masks, gloves, and shoe covers.
Before adding face shields to their protective gear, 12 health workers got infected between May 3-15 (all 62 workers had tested negative on May 1). During this period, they had visited 5,880 homes with 222 infected residents. Home visits were subsequently suspended on May 16.
Given the design of their study, the researchers believe that the 12 health workers who tested positive must have gotten infected during their visits. “Because the first worker became symptomatic 13 days after beginning home visits and workers had no contact with family, coworkers, or the public, there is no known alternative source of infection for the workers except the asymptomatic contacts of SARS-CoV-2 patients.”
Face shields (made of polyethylene terephthalate with 250-μm thickness) were then given to the remaining 50 non-infected workers who resumed home visits on May 20. Despite visiting over 18,000 homes — which included 2,682 infected residents — between May 20 and June 30, none of the workers contracted the virus.
“The face shields may have reduced ocular exposure or contamination of masks or hands or may have diverted movement of air around the face,” the researchers suggested in conclusion.