Face Shields Staved Off COVID-19, HAIs at Texas Hospital

A program of universal face shields for healthcare personnel (HCP) at one Texas hospital was not only tied to fewer COVID-19 infections, but fewer hospital-associated infections (HAI), a researcher said.

In the pre-intervention period, from April 17-July, 5, HCP infection rate increased from 0% to 12.9%, but it declined to 2.3% during the intervention period, July 6-July 26, reported Mayar Al Mohajer, MD, MBA, of Baylor College of Medicine in Houston.

Moreover, in the pre-intervention period, HAI cases rose from 0 to 7, but dropped back down to 0 during the intervention period, he reported in a late-breaking presentation at the virtual IDWeek.

Al Mohajer noted how the approximately 500-bed hospital, with over 6,000 employees, implemented infection control measures in April. This included surveillance testing and biweekly testing of HCPs in “high-risk units,” such as the emergency department, the transplant unit, and the COVID unit. Asymptomatic patients were also tested on admission and day 7.

Al Mohajer described Texas’ reopening, which culminated in phase 3 on June 12, where restaurant capacity was increased to 75% and college and professional sports were increased to 50% capacity, in addition to other venues that were open. In the first week, a cluster of 112 HCPs tested positive thanks to clusters in two ICUs, the operating room, and environmental services. Most started in the community and spread staff to staff, he said. They also had seven HAIs, or 3.4 cases per 1,000 patient days.

While the hospital had already implemented most of the CDC’s infection prevention measures, the one thing they had not done was implementing face shields. Face shields “reduce the potential of autoinoculation, protect the portal of entry,” and prior research has shown that they aided in preventing aerosol transmission, he noted.

“When they [studies] looked specifically at small particle aerosols, face shields blocked 68%” of them, he said.

On July 6, the hospital recommended universal face shields for all HCPs, but “we went beyond what the CDC recommended,” Al Mohajer said, explaining that the face shields were for HCP-to-patient interaction and HCP-to-HCP interaction.

Al Mohajer and colleagues found that, over the study period, 246 of 6,527 employees tested positive for SARS-CoV-2 (3.8%). Following the intervention, change in predicted proportion positive in week 13 dropped from 22.9% to 2.7% (P<0.001).

For HAIs, a total of 25 were identified over the study period — 16 possible (occurring in day 5-13 of admission) and nine confirmed (occurring at least 14 days afterwards). The change in predicted HAI rate fell from 8.4 to 1.7 per 1,000 patient days (P<0.001).

While Al Mohajer noted that Texas implemented several measures at the same time as the hospital’s intervention, such as mandatory mask wearing and limiting of elective procedures, it is a possible, though unlikely confounder.

“Numbers in … Texas didn’t really go down until late July, while our numbers went down in the first week of July,” he said.

Al Mohajer also said that after the study, researchers in India found similar results for community health workers after adding face shields to face masks. Their results supported universal face shields as part of a “multifaceted approach” to prevent SARS-CoV-2 transmission, especially in areas with high community spread, he added.

“It’s so important to keep everyone as healthy as we can,” said Joshua Nosanchuk, MD, of Albert Einstein College of Medicine in New York City, who moderated the IDWeek session, but was not involved with the research.