McMaster-led research shows surgical masks as effective as N95 in health-care settings

Surgical masks are as safe as the N95 masks in preventing the spread of COVID-19 among health-care workers, a study led by McMaster University researchers showed.

The study, published in the American College of Physicians journal, tracked more than 1,000 health-care workers at 29 sites across Canada, Egypt, Israel and Pakistan between May 2020 and March 2022 to evaluate the effectiveness of both surgical masks and N95s.

Dr. Mark Loeb, lead author and molecular medicine professor at McMaster University, told The Spectator, the study is the only randomized controlled trial of the N95 respirator compared to a surgical mask," offering the highest standards of evidence, including when the spread of Omicron virus was on the rise.

At least 1,009 health-care workers, who were working closely with COVID-19 patients, were examined with N95 and surgical masks in a randomized setting for 10 weeks.

The study shows that there certainly was not much of a difference between the two" masks, said Loeb.

He noted the outcome of the study should be of interest to health-care workers, decision-makers, policy-makers and governments.

In 2020, Loeb and his team received nearly $1 million in funding for the research. The research was funded by the Canadian Institutes of Health Research, the World Health Organization and the Juravinski Research Institute.

Loeb said the study is especially important" for low- and middle-income countries because they can look at the difference between the two groups of surgical masks versus N95 respirators ... and make informed decisions based on their resources."

Throughout the pandemic, some countries faced shortages of N95 respirators, while procuring the equipment was not affordable.

Previously, conflicting recommendations on the use of N95s throughout the pandemic were seen, Loeb said.

The U.S. Centers for Disease Control and Prevention recommended N95s for routine care of patients with COVID-19, while the World Health Organization and the Public Health Agency of Canada first recommended surgical masks, he said.

The recommendations by WHO were later changed to either surgical masks or N95, while the Public Health Agency of Canada recommended N95s.

In December 2020, the Ontario Nurses' Association advised its members not to participate in Loeb's study, calling the trial unethical" for placing health-care workers at risk for the sake of research."

Ritika Dubey is a reporter at The Spectator. rdubey@thespec.com