COVID Update: High rate of transmission, more hospitalizations and a wild card

January 11, 2023
Red globes on a blue background. The globes have lighter blue spikes sticking out from them.
An illustration by the National Institute of Allergy and Infectious Diseases of coronavirus particles.

During what the South Carolina Department of Health and Environmental Control is calling a surge in COVID cases, new number crunching gives an updated picture for much of the state. The Medical University of South Carolina’s COVID-19 tracking team just released its weekly assessment, and its leader summed up its findings this way: “There’s a high rate of transmission happening.”

That leader, Michael Sweat, Ph.D., also noted a couple of other factors to keep an eye on for the next several weeks during the surge: rising hospitalizations and the variant XBB.1.5.

New numbers

Sweat’s team takes data from DHEC, analyzes it and offers perspective in weekly updates published online. This week’s numbers suggest that what’s been happening in North Carolina, which has high levels of COVID, according to the Centers for Disease Control and Prevention, is moving geographically into South Carolina.

The MUSC team found:

  • The Charleston Tri-county area, which includes Berkeley, Charleston and Dorchester counties, saw a 2% increase compared with the previous week. It had 22 reported cases per 100,000 people. Sweat said the real number is probably at least six times higher since self-tests aren’t included in the count.
  • The Florence area, which includes Florence, Marion, Darlington and Williamsburg counties, had a 32% jump in cases. Sweat’s team called that a rapid increase. It had 36 reported cases per 100,000 people.
  • The Lancaster metro area, which includes Lancaster and Chester counties, dropped 5%. It had about 31 reported cases per 100,000 people.
  • The Midlands area, which includes Fairfield, Kershaw and Richland counties, went up 23%. It had 41 reported cases per 100,000 people.

Most of South Carolina has high or medium levels of COVID right now, according to the CDC. Areas on the map below colored orange/red are high, yellow are medium and green are low.

Map of South Carolina. Most of the state is colored red/orange or yellow. 
CDC map showing prevalence of COVID-19 in South Carolina on January 11, 2023.

“For red, the CDC recommends you wear a mask. And for yellow, they say it’s optional. But if you’re around anybody who is at risk, then you should wear a mask. I think we’re going go to red soon,” Sweat said, referring to the Charleston area.

“The data is speaking. It’s saying we’re probably at a point where it would make sense for people to take precautions for a short period of time. These peaks typically come relatively quickly. You know, it’s probably six to eight weeks.”


Sweat said one key component of the CDC’s color-coded alerts is based on hospitalizations for COVID-19, and that is what is primarily turning so many counties to red status. That’s important right now because hospital numbers are on the rise again. “We had a 31% increase in hospitalizations of people with COVID-19 last week in the Tri-county area.”

Nationally, hospitalizations are up, too. The CDC’s most recent numbers showed a 16% increase compared with the previous week.

“We’re beyond the point where you’re going to see hospitals collapse, which parts of the country went through, more or less. And the mortality is much lower than it once was. But COVID is still killing more than 500 people a day in the United States. It’s way more deadly than flu,” Sweat said.

“Most people who are younger, particularly if they’re vaccinated or have had an infection, will have mild cases. But they can pass it along to more vulnerable people who are really at risk.”

XBB.1.5, “the Kraken”

A new subvariant nicknamed “the Kraken” – a fearsome mythical sea monster that rises up unexpectedly – may be driving some of those hospitalizations. “It’s a real wild card,” Sweat said.

“That variant’s parent, XBB, when it hit Singapore, it just exploded. They had higher vaccination rates than we do, and they had prior waves, too. So they were probably better off than we were. And they just had explosive – a massive outbreak occurred in the country very quickly.”

XBB’s offspring, XBB.1.5, is already in the United States. “It then popped up in the New England area – in New York and New Jersey and Vermont. And now it’s 27.6% of all cases in the U.S. but over 70% now in the New England area. I mean, it grew so quickly. It’s growing like Omicron did. But even worse.”

It’s unclear if the new subvariant has arrived in South Carolina. “It’s very transmissible, and it outcompeted the other variants. So that’s what you would expect to see. There’s no question we’re going to have it. We may have it now. We just don’t know because we aren’t doing much sequencing.”

Sequencing involves looking at the genetic makeup of COVID samples to see what strain they are.

Early studies suggest bivalent vaccine boosters should help in the fight against the new subvariant. But Sweat said unfortunately, too few people are getting them. “Just getting that one more dose would make a big difference.”

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