Microbiologist weighs in on how to know COVID-19 is becoming endemic

Many Americans are taking off their masks, now that new infections with the COVID-19 omicron variant are plummeting.

Still, microbiologist Amber Schmidtke, Ph.D., chair of the Department of Natural Sciences and Mathematics at the University of Saint Mary, says she will keep wearing her KN95 in public, indoor settings, as a way to protect herself and vulnerable individuals around her.

"Because there are a lot of immune compromised people in and around us, and those people are still at very high risk of the complications that might come with catching COVID-19, even if they've been vaccinated and boosted," Schmidtke says. "Since we can't tell from looking at a person whether they're immunocompromised, it does make sense to continue wearing masks if you're in a congested indoor space."

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With cases falling, Schmidtke says, the risk of getting infected is dropping, at least for now.

"The risk is a lot lower after we have these waves because we have a built-in, temporary sort of herd immunity afterwards," she says. "So, you'll see this lull in disease that happens in between, and really that's the time if you're a person who has been putting off a major surgery, or something like that, this is the time to try to get that scheduled."

It is also a good time, she says, for parents to get their children caught up on their routine vaccinations.

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"For most of us, I don't think it's a license to go out and live your best life without any precautions, but you can afford to take more risks than you could have a month ago," Schmidtke says.

So, what about booster shots?

Do fully-vaccinated people still need an extra shot, if new infections are decreasing?

"It's, of course, an individual choice," Schmidtke says. "I would always encourage the vaccine, just because it gives your immune system just another bit of practice to recognize the treat and to respond to it.  We have seen reinfections happen. Even if you get infected before, you get infected a second time. So, we don't know how long that immunity lasts. That's another reason to consider getting a booster, if you haven't gotten it."

The U.S. Food and Drug Administration is monitoring pandemic data from around the US and the world, to determine whether to recommend a second booster shot down the road.

"I fully anticipate we're going to need regular boosters, kind of like we do with the flu vaccine," Schmidtke says.

She also believes the US should be prepared for another surge.

"I think it would probably happen in the summer," Schmidtke says. "This virus seems to operate in a twice-a-year cycle, (in the winter and) in the summer, when the climate is unpleasant enough that people tend to gather inside.  So, I wouldn't be surprised if we see something again this summer."

One question she has been thinking a lot about, she says, is when we will know we are on the other side of the pandemic.

"If we can make it out of the summer without a surge, if we can make it through the next holiday season without a surge, then I think we're talking about putting this a little bit behind us," Schmidtke says. "But, unfortunately, what we've seen is that each successive wave seems to get bigger than the one that preceded it.  So, we're not on that downhill slope, when it comes to the overall cadence of the pandemic."

The federal mask requirement for airline passengers and other travelers is set to expire on March 18, 2022.

The Biden Administration has not indicated whether it will extend the requirement or allow it to lapse as cases drop.

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