Becker's Clinical Quality & Infection Control

7 INFECTION CONTROL Consistent indoor mask use cuts COVID-19 risk, real-world CDC study finds By Erica Carbajal P eople who report they always wear a mask or respirator in indoor public settings were less likely to test positive for COVID-19 than people who did not, according to the CDC's Feb. 4 Morbidity and Mortality Weekly Report. Researchers randomly selected California residents who received a COVID-19 test result from Feb. 18 to Dec. 1, 2021. They assessed mask or respirator use among 652 participants who tested positive and 1,176 participants who tested negative. All participants had self-reported being in in- door public settings during the two weeks before testing and had no knowledge of exposure to someone with a confirmed or suspected infection. ose who reported always using a face mask or respirator indoors compared to those who said they never masked in- doors were less likely to test positive for COVID-19, with an adjusted odds ratio of 0.44 percent. e protection increased as the quality of mask increased, based on an anal- ysis of 534 participants who reported their mask type. ose who reported consistently wearing a cloth mask had 56 percent lower odds of testing positive. e figure rose to 66 percent for surgical masks and 83 percent for N95 and KN95 respirators. Laboratory studies have demonstrated masks' effectiveness, though few studies have focused on their real world efficacy, the report said. "ese findings reinforce that in addition to being up to date with recommended COVID-19 vaccinations, consistently wear- ing a face mask or respirator in indoor public settings reduces the risk of acquiring SARS- CoV-2 infection," researchers said. "Using a respirator offers the highest level of personal protection against acquiring infection, although it is most important to wear a mask or respirator that is comfortable and can be used consistently." n Yale researchers develop personal COVID-19 exposure detector By Erica Carbajal A team of researchers from New Haven, Conn.-based Yale University have developed a wearable air sam- pler device meant to monitor personal exposure to the coronavirus. The team first tested the polydimethylsiloxane-based air sampler in a rotating drum experiment, according to findings published Jan. 11 in Environmental Science & Technology Letters. Polymerase chain reaction testing detected virus in the sampler after it was in the rotating drum, which contained aerosols laden with a surrogate virus similar to SARS-CoV-2. Researchers then embedded the passive sampler in a wearable clip design. Sixty-two participants wore the samplers for five days, after which PCR testing detected the virus on five (8 percent) of them. Of those, four were worn by restaurant servers and one by an employee at a homeless shelter. The highest viral loads were found in two of the clips worn by the restaurant servers. "Our findings demonstrate that PDMS-based passive sam- plers may serve as a useful exposure assessment tool for airborne viral exposure in real-world high-risk settings and provide avenues for early detection of potential cases and guidance on site-specific infection control protocols that preempt community transmission," researchers said. n Why some hospitals ask patients, visitors to ditch N95s By Mackenzie Bean H ospitals across the country often ask patients and visitors to swap out their N95s with surgical masks in line with CDC guidelines, which public health experts say are outdated, Politico reported March 16. Many health systems — such as Northwestern Medicine in Chicago and Munson Healthcare in Traverse City, Mich. — ask patients to replace or cover their masks with a surgical mask supplied by the facility for quality con- trol, according to the report. Most clinicians in hospitals also wear surgical masks when interacting with patients, per CDC recommendations. Studies show N95 masks offer better protection against airborne viruses, as they create a tighter seal around the face. Health experts have expressed concern that broad use of surgical masks in hospitals puts vulnerable people at higher risk of contracting COVID-19. "It's baffling," Ezekiel Emanuel, MD, PhD, a bioethicist at the University of Pennsylvania in Philadelphia, told Politico. "This is something where the CDC has been on the wrong side for a long time." The CDC and the White House's COVID-19 response team declined Politico's request for comment. However, the entities have previously said surgical masks offer sufficient protection against the virus in many situations within hospitals. n

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