Researchers put surgical masks to the test
DALLAS, U.S.: Owing to constant face-to-face interaction with members of the public, dentists and other health care professionals are at a greater risk of contracting contagious diseases. One of the most effective and simplest ways to mitigate this risk is by the use of a surgical mask; however, for a number of years now, professionals have debated whether the standard mask or the N95 mask is more effective. There may now finally be an answer: the largest study into the masks thus far has reported no significant difference in their effectiveness at preventing influenza among health care personnel.
During the 2009 outbreak of the H1N1 virus in the U.S., the Centers for Disease Control and Prevention recommended using the tighter-fitting N95 mask to decrease the risk of infection. This recommendation played a part in sparking the debate around the two different masks, but up until now, no large-scale study had been done to test their effectiveness.
Over the period of four flu seasons between 2011 and 2015, the researchers collected data on the masks’ effectiveness at protecting health care workers from flu and other respiratory viruses. “This study showed there is no difference in incidence of viral respiratory transmission among health care workers wearing the two types of protection,” said senior author Dr. Trish Perl, Chief of the University of Texas Southwestern Medical Center’s Division of Infectious Diseases and Geographic Medicine. “This finding is important from a public policy standpoint because it informs about what should be recommended and what kind of protective apparel should be kept available for outbreaks.”
The results showed that, out of the 2,400 health care workers who took part in the study, 207 laboratory-confirmed influenza infections occurred in the N95 group versus 193 among the medical mask wearers. In addition, there were 2,734 cases of influenza-like symptoms, laboratory-confirmed respiratory illnesses, and acute or laboratory-detected respiratory infections in the N95 group, compared with 3,039 such events among the medical mask wearers.
More studies are likely to come out of this recent investigation, according to Perl, and she said she would next look into the dynamics of virus transmission to better understand how respiratory viruses are spread.
The study, titled “N95 respirators vs medical masks for preventing influenza among health care personnel: A randomized clinical trial,” was published on Sept. 3, 2019, in JAMA.