MINNEAPOLIS — With mask mandates making a comeback at some schools, workplaces and public spaces, even masking experts understand why many people may be confused or frustrated.
"I am disappointed too, but we have to follow what we're seeing in front of us," said Dr. Elie Berbari, Chair of Infectious Diseases for the Mayo Clinic. "We have to supplement the vaccine strategy with something else, and one of the best tools we have is masking."
Dr. Berbari says the call for mask mandates, even for the vaccinated, is due to the new threat posed by the delta variant. Though COVID vaccines are still likely to protect you from getting sick from delta, he says the variant is about 1,000 times more infectious, meaning others aren't as protected from you.
"You might get the virus, transmit the delta virus, without you ever knowing that that's the case," Dr. Berbari said.
A newly published study from the Mayo Clinic and the University of Minnesota suggests that simple masks can help cut that transmission rate to nearly zero.
Chris Hogan, a professor of aerosol science at the University of Minnesota, says the study found that anything that covers the mouth and nose works pretty well in social settings that last a few minutes.
"The masks have, what's called a diffuser effect," Hogan said, pointing out a video from the study that used smoke to help show how different masks impact airflow. "When someone wears a mask, we don't see a jet of smoke. What we actually see is the flow going up and away, and that's what I mean by a diffuser effect."
The study also measured and quantified that diffuser effect by using two mannequins that simulated the spread of respiratory droplets at various distances. According to the study, a single mask on the exhaling "source" mannequin cut transmission by 90%. When researchers added masks to both mannequins, transmission fell by 99.5% -- regardless of the distance and the mask they used.
"Even if the mask leaks, the flow has to kind of make this crazy bend, to go out the leak," Hogan said. "The particles can't do that, they can't make that turn."
Meaning just a little piece of material can mean big peace of mind.
"We're wearing it to protect people from us potentially being infectious," Hogan said. "So I view it as a little bit of a sense of duty to do that."