Subvariants raise doubts about previously predicted dip in COVID cases

July 13, 2022
Two purple blobs with green circles around their edges,
Coronavirus particles, green, within a heavily infected nasal cell. Image from National Institute of Allergy and Infectious Diseases

The fast-spreading Omicron subvariants BA.4 and BA.5 could jeopardize a previously predicted decline in COVID cases for the Charleston Tri-county area. Michael Sweat, Ph.D., leads the Medical University of South Carolina’s COVID-19 Epidemiology Intelligence Project. “We could see some big numbers,” he said.

This week’s update from his team found reported COVID cases rose 9% for the Charleston Tri-county area. That’s 36 cases per day per 100,000 people. Sweat said the actual number of cases is likely much higher. Many aren’t included in the update because people are testing at home and their results aren’t reported to the state.

The increase comes as BA.4 and BA.5 spread across the country, raising the possibility of a sustained surge. “The vast majority of people haven't had a vaccination in over a year and haven't been boosted. The big fear is that we will suddenly go into a massive surge as the months go forward. And there'll be so many cases that it will affect the economy.”

That’s the big fear – but Sweat said it may not be realized in the immediate future, if at all. “Things often go slower than you expect. You think, ‘Oh, we're really primed for something.’ But it often kind of goes slowly. It could be, we're going to chug along at this rate over summer and even drop. And then all of a sudden we're going to see some big outbreak happening.”

The threat of an outbreak is in part due to how good the subvariants are at getting around antibodies from previous infections. “If you had Omicron when most people did, you could get BA.4 or BA.5. It will not protect you from getting infected.”

Neither will the way a lot of us are living right now, Sweat said. “We're now at a point where the majority of people, by far, don't take any precautions. They just live their lives like they did before COVID.”

Dr. Michael Sweat 
Dr. Michael Sweat

But Sweat said there’s a key factor in our favor, at least for now. The numbers of hospitalizations and deaths as a proportion of the number of cases are at record lows for the pandemic. “That's a byproduct of so many people having been infected, and then the fact that a lot of people got vaccinated. But there's a continued worry about sort of waning immunity.”

MUSC Health had about 80 people hospitalized with COVID systemwide in the most recent update, a number that’s rising but manageable, Sweat said.

But Sweat, a professor in the College of Medicine at MUSC, an adjunct professor at the Johns Hopkins Bloomberg School of Medicine and a former research scientist with the Centers for Disease Control and Prevention, is also tracking another concern that he wants people to be aware of. It was the focus of a big study by the Department of Veterans Affairs.

VA researchers followed about 5 million people who have had COVID. “They're looking at repeated infections and what happens to people as you get repeatedly infected. And the takeaway was the more you get infected, the worse the outcomes start to become,” Sweat said.

“A lot of people think, ‘Oh, if I get it twice, I'm even more protected.’ But there's a cumulative impact. Your chances of ending up in the hospital go up five to seven times with a third infection. The risk of a cardiovascular side effect goes up three or four five times. It's not good to think that COVID is always just a minor thing. The risk gets amplified over and over.”

Despite that risk, Sweat said living with the threat of COVID as the virus continues to mutate doesn’t have to mean all or nothing when it comes to taking precautions. “I do think the mindset is that it's binary. Either you're living in a cave or you're just living your life. But I think it's really not. It's a continuum. If you're thoughtful, you can still live a pretty normal life. You may give up a few things. Like maybe for me, it's eating in restaurants,” Sweat said.

“Thinking that you’re either kind of a nut and always wearing a mask and never touching anybody and never doing anything, or you're just not, that’s not how it has to be. There is the potential for mitigating it and still living a normal life. And I feel like that message doesn't get out to people.”

It’s a message that may maintain its importance as the virus continues to mutate. “Every time these variants come along, we get another wave. It does appear to me that they're coming more frequently, by the way — the variants. The time from Alpha to Delta was almost a year. Then Delta to Omicron was nine months. Now we’ve got this whole Omicron lineage. It's coming faster. We're going to see another wave of infections. How quickly that'll happen, I don't know.”

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