‘The most contagious variant:’ Will newest version of omicron lead to another COVID-19 surge?

RALEIGH, N.C. (WNCN) — We’ve seen several versions of the omicron variant and in every week of 2022, one of them has accounted for the most COVID-19 cases in North Carolina.

Now comes the latest one: BA.5, described by two local leading infectious disease experts as the most catchy of all.

It made up more than half of all new cases across the country last week, and is poised this week to take over as the dominant strain in the state.

“The most contagious variant that we’ve seen in the pandemic,” said Dr. David Montefiori, an infectious disease specialist at the Duke University School of Medicine.

That’s because of its mutation to the spike protein — the target of antibodies produced from both the vaccines and previous infections. That evolution helps it elude those antibodies.

What it hasn’t led to — at least, not yet — are significantly more people checking into hospitals or dying, and that’s a good sign for what the next surge could look like.

“The virus is evolving, not to be more lethal — which is great news,” said Dr. David Wohl, an infectious disease specialist at the University of North Carolina School of Medicine. “But the bad news is, it’s evolving to be more transmissible.”

Montefiori says it’s “causing another wave of infections” but called the increase in hospitalizations “very, very modest rise compared to what we’ve seen in the past.”

What’s most remarkable is how quickly it has become the dominant strain.

It accounted for 38 percent of the state’s sequenced samples during the last week of June. Just two weeks earlier, it made up just 15 percent.

And in reality, those rates could be even higher — but the prevalence of unreported at-home tests makes getting a trustworthy case count even more of an impossibility.

“We’ve always known that we may be underestimating COVID-19 even by a factor of 10, even in the best of times,” Wohl said. “It’s much, much, much worse right now. We have no idea how much COVID-19 is being spread.”

And an even smaller share of those samples are sequenced to figure out the variant.

Of the 23,544 cases reported to the state Department of Health and Human Services during the week that ended June 25, just 391 — or 1.6 percent — were sequenced.

“It is more difficult these days to have accurate numbers,” Montefiori said.

But how do we know how BA.5 ultimately will compare with those other subvariants when the numbers we use to measure them will be less accurate?

North Carolina is averaging about 3,500 new cases per day, according to the official case count from NCDHHS. But modelers from the University of Washington project more than three times as many North Carolinians — more than 11,000 — are actually catching the virus every day.

“The answer is yes, there’s a lot of COVID transmission,” Wohl said. “But the great news is most of those people are saying, ‘I had it, and it put me in bed for a few days.’ …

“It’s like it’s becoming less and less consequential,” Wohl continued. “Remember, that was the goal. We wanted to make this not an existential threat. For many of us, most of us, it’s not. If we want to keep it that way, I am telling you boosting is the way to go.”

The main omicron variant and its spawn — BA.2 and BA.2.12.1 — have each taken a turn as the state’s dominant variant in 2022, and BA.5 is on the verge of joining them.

That raises a question: What is it about omicron that is spinning off so many surge-causing subvariants in the first place as opposed to what Wohl described as “whatever comes next in the Greek alphabet?”

“I think what we may be seeing is the virus getting more and more funneled to a more narrow width with which it can mutate,” he said. “There's only so many tricks this virus can throw at us. … How much further can it get? You know, there's a limit to even what the this virus can do.

“There may be some emerging variant that is horrible, but it just hasn't been able to find a toehold in the U.S. due to our immunity or other things. … We’ll see, can we continue to paint this into a corner with the built-up immunity we've had?”