A surgical mask and an N95 mask hang on display for sale at a pharmacy. (Sean Gallup | Getty Images)
As public health professionals brace for the spread of the omicron variant of the coronavirus, masking may be more important than ever, a Milwaukee doctor said Tuesday.
“You want to also think about what kind of mask you’re wearing,” said Dr. Ben Weston, Milwaukee County chief health policy advisor and a professor at the Medical College of Wisconsin, speaking at the county’s weekly COVID-19 briefing. That’s true with delta, still the most widespread form of the SARS-CoV-2 virus, he said, and it’s true with omicron, the newest variant of concern according to public health scientists.
“Seeing that omicron is more transmissible than delta, that means cloth masks are not going to be as effective as they were,” Weston said. Medical grade masks such as surgeons use are a step up, he said, and N-95 or KN-95 masks (the numbers measure their efficiency at blocking microscopic particles or droplets) are better still.
“Absolutely, this is a time for people to be wearing masks when you go to the grocery store, when you go to the mall, when you’re indoors in public,” Weston said. “Please just wear a mask. It’s easy. It’s simple, and it keeps you and one another safe.”
The omicron variant of the SARS-CoV-2 virus that is responsible for the COVID-19 pandemic has only just begun to appear in Wisconsin. Early reports — which still need to be confirmed from more data — indicate that omicron might spread even faster than the delta variant, he said. Delta remains the dominant form of the virus in Wisconsin, the U.S. and much of the world.
The biggest uncertainty about the new variant is how well current COVID-19 vaccines will protect people from infection or severe disease caused by omicron. Early indications are that natural immunity — the kind a person gets from surviving a bout with the virus rather than from a vaccine — is a weaker defense.
“There is preliminary evidence, but it’s pretty compelling evidence that past infection may not be as protective with omicron,” Weston said. It’s too soon to judge whether the vaccine is also weaker, he added, but based on previous variants, “we may get not quite as great a level of protection but still quite good protection.”
For that reason, getting vaccinated remains essential, public health officials say, as does getting a booster shot for fully vaccinated people who are eligible.
One reason it might be harder for a vaccine or previous COVID-19 illness to ward off omicron is the difference between the new virus and its predecessors — a distinction that shows up in the spike protein found on the surface of the virus.
“Omicron has over 30 mutations on the spike protein, the part that attaches to our cells — 30 mutations on the spike protein alone,” said Weston. The emergency physician has posted a video on social media comparing virus mutations to changing how a toy airplane made with Legos looks by moving the plastic bricks around on the plane.
“If you swap out the right Lego, it could completely change the function of the plane,” he said. “One Lego swapped out, or one mutation in the case of the virus, can change the structure and make a big difference in how it infects us, how it spreads and how it evades immunity.”
With faster spread and questions about how easily a variant might break through the immunity barrier, “this makes masking, distancing and ventilation more relevant than ever,” Weston said.
Vaccination combined with multiple forms of protection provides broader protection against the spread of the virus, according to Darren Rausch, health officer and director of the Greenfield Health Department in suburban Milwaukee. The value of combining several measures at once shows up in the different rates of COVID-19 infection between Milwaukee and its suburbs.
“There have been times where the city of Milwaukee had a higher case growth rate than the suburban communities,” Rausch said. “And we’ve seen times like now when the suburban communities have higher case growth rates.”
Yet the suburban areas of Milwaukee County have higher vaccination rates than the city does, he said — indicating that when the transmission of the virus is active, even vaccinated people will benefit from following other mitigation practices.
“When you go to certain communities, it’s easy to feel like the pandemic is over,” Rausch said. “Because no one’s wearing masks, no one is doing the things that we know that keep them safe. But if you go into a community, say, like Madison, you see lots of masks, you see signage, you see reminders on stores and businesses [to wear masks and maintain physical distance]. And so those characteristics are really going to be driving what we’re seeing in cases.”
GET THE MORNING HEADLINES DELIVERED TO YOUR INBOX
Our stories may be republished online or in print under Creative Commons license CC BY-NC-ND 4.0. We ask that you edit only for style or to shorten, provide proper attribution and link to our web site. Please see our republishing guidelines for use of photos and graphics.