‘Every summer we’ve had a wave.’ What to expect from COVID as weather warms

June 05, 2024
Ocean wave in the colors blue and white.
COVID has come in waves since the early days of the pandemic. But it's not the only virus on an MUSC scientist's mind this summer.

COVID analyst Michael Sweat, Ph.D., predicts we’ll see a COVID-19 increase as the weather warms. “It’s going on five years now. Every summer, we’ve had a wave. It’s not as bad as the winter wave, but it definitely happens.”

Sweat, leader of the COVID tracking project at the Medical University of South Carolina and a former research scientist with the Centers for Disease Control and Prevention, said the timing is up in the air. “You don’t know exactly when it’s going to happen. Sometimes it’s right around the 4th of July, and then sometimes it’s later, like into August. So we’ll see. But I definitely think we’re going to see another bump up occurring in the weeks ahead.”

Flirting with new variants

If it does, it will occur in the context of a new group of variants nicknamed FLiRT. They’re descendants of the Omicron variant.

Dr. Michael Sweat 
Dr. Michael Sweat

“Every variant is worse than the one before. It means it’s got an advantage in transmission. That’s why it becomes prominent. But that’s not necessarily the case as far as symptoms go,” Sweat said.

“Right now, the KP.2 FLiRT variant, of Omicron lineage, is on top with about 28% of estimated cases. But that doesn’t seem to be having much impact on severity.”

In other words, it’s not making people any sicker than previous variants. And case numbers so far are low, Sweat said. So now’s a good time to look ahead. That means making sure people have at-home tests. Yes, Sweat said, it’s still important to test.

“One reason is because you can spread it to other people, and there’s a lot of people who could really get sick and die from it. I think knowing if you have it, you take some basic precautions for a relatively short time, you know, wear a mask, stay away from people,” Sweat said.

“That’s one reason. And the other one is if somebody’s at a higher risk of getting seriously sick and they know they have COVID, they could take the antiviral drug Paxlovid, which can shorten the duration and severity of COVID-19. But you have to take that within five days of symptom onset. It’s more effective the quicker you take it. So for somebody who’s elderly or has some immunocompromised status, a lot of comorbidities, it’d be smart to test if you think you have it.”


When it comes to trying to keep from getting COVID, Sweat had this take. “It’s a tricky question to answer because everybody has their own risk tolerance, right? I would say there’s pretty good confidence that we’re going to have increases in the summer,” he said.

“So if you’re really worried in general, we all know the preventive measures, right? Which is masking and all that kind of stuff.I think things have changed, and we need to realize that we have a lot more immunity. I’m well vaccinated. But other people do worry, and that’s appropriate for them.”

Other potential threats as scientists keep an eye on COVID-19

Sweat said other coronaviruses continue to be a concern in addition to COVID-19. “It keeps happening. Every nine years, basically, we’ve had a new coronavirus that has come out, some of them very deadly like MERS.” MERS stands for Middle Eastern Respiratory Syndrome.

“MERS has 60% mortality, but it’s so deadly it didn’t spread widely. It’s still present in Saudi Arabia, in that part of the world, but it doesn’t seem to spread much beyond that. But then the original SARS was the nine years before that. So it’s just a reality that coronaviruses are a concern, just like flu viruses are a concern. So we’re going to have to keep monitoring those,” Sweat said.

Sweat, a professor in the College of Medicine at MUSC and an adjunct professor at the Johns Hopkins School of Public Health, said the bird flu is also a worry. 

“It’s been detected in the U.S. now with dairy cows, and they think it’s being transmitted through the udders. There have been, I think, three now people infected, or maybe four. The most recent one was a bit of a worry. The first two got conjunctivitis, an inflammation of the eye, and it was mild, and they gave them antivirals, and it cleared up. The third one, though, got respiratory symptoms,” Sweat said.

“That’s when you get really worried in epidemiology. Because that’s what really spreads things. So, you know, the virus will adapt and mutate and take advantage of host issues. If it starts to do that, it’s a concern.”

So Sweat’s virus tracking continues. To get the latest weekly updates from his team, check out its web page. We’ll post stories on the MUSC Catalyst News web page as conditions warrant.

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