Mask Users 40% More Likely to Be Infected with COVID Than Non-Mask Users: 3,209-Participant Randomized Trial Published in Peer-Reviewed Journal 'Epidemiology & Infection'
"Our findings suggest that wearing a face mask may be associated with an increased risk of infection."
A study published last month in the peer-reviewed medical journal Epidemiology & Infection examined the association between face masks and risk of infection with SARS-CoV-2.
The study authors analyzed data from 3,209 participants in a randomized trial exploring the “effectiveness of glasses in reducing the risk of SARS-CoV-2 infection.”
Face mask use was determined by participants’ responses to a follow-up survey.
“In the end-of-follow-up survey, we asked the participants about their face mask use during the study period,” the study reads. “Participants reported on face mask use by selecting one of six responses to the question ‘How often over the last 2 weeks have you used a face mask when you have been close to others outside your home?’ (1) Always; (2) Almost always (at least 75% of the time); (3) Often (50–75% of the time); (4) Sometimes (25–50% of the time); (5) A few times (up to 25% of the time); and (6) Never.”
The study found that people who wear face masks “often or sometimes” reported getting COVID-19 33% more than those who rarely or never wear them.
Significantly, the rate was 40% higher for those wearing masks “almost always or always.”
“We found that the incidence of self-reported COVID-19 was 33% (aRR 1.33; 95% CI 1.03-1.72) higher in those wearing face masks often or sometimes, and 40% (aRR 1.40; 95% CI 1.08-1.82) higher in those wearing face masks almost always or always, compared to participants who reported wearing face masks never or almost never,” the authors confirm.
The authors conclude by emphasizing their “findings suggest that wearing a face mask may be associated with an increased risk of infection.”
They argue that public mask mandates are based on “low certainty evidence.”
“Recommendations to wear face masks in the community are largely informed by low certainty evidence from observational studies,” they state. “More randomized trials or quasi-experimental studies are needed to improve our insights on the effectiveness of face masks for protection against the transmission of respiratory pathogens.”
The study authors were not able to determine the reason masking increases the risk of COVID-19 infection.
“We believe the observed increase in the incidence of infection associated with wearing a face mask is likely due to unobservable and hence nonadjustable differences between those wearing and not wearing a mask,” they write. “Observational studies reporting on the relationship between face mask use and risk of respiratory infections should be interpreted cautiously, and more randomized trials are needed.”
Despite these findings, the Centers for Disease Control and Prevention’s (CDC) new director Mandy Cohen is advising Americans to wear masks this holiday season.
In a video posted to the agency’s X (formerly Twitter) account, Cohen urged people to “[u]se additional layers of protection like avoiding people who are sick, washing your hands, improving ventilation and wearing a mask.”