The deadly delta COVID variant ravaged MS, then all but disappeared. What happened?

Delta was the dominant variant of COVID-19 for months, until omicron showed up in Mississippi in early December.

The Mississippi State Department of Health announced the first case of omicron in Mississippi on Dec. 6, and by Christmas omicron was half the cases in the state. By Jan. 11 — a little over a month since it began — health department officials said virtually every new case was omicron.

So what happened to delta? Did omicron overpower and bully it away?

Dr. Katherine Baumgarten, medical director of infection control and prevention at Ochsner Health, explains what happened to the delta variant.

With most variances, including the flu, she said, one strain starts to take over and is more easily transmitted.

“The other strain that was there in the past kind of fades out or fades away,” she said. “It doesn’t mean that it’s gone completely — it just means that most people will have immunity. “

Omicron came in and pretty much chased delta away.

“Remember, delta did that with the very first and native variant that we saw,” said Dr. Robert Hart, chief medical officer at Ochsner Health. He said delta basically put the first COVID-19 virus strain down “and that kind of took over the U.S.,” he said.

The vaccine worked well to combat delta, Baumgarten said.

“So delta doesn’t ever completely go away,” she said. “But omicron has shown that it has the ability to take hold in the community and that’s what it’s done.”

50 days of omicron in Mississippi

Nov. 20 — 95% of all cases of COVID-19 were the delta variant

Dec. 6 — First case of omicron announced in Mississippi

Dec. 18 — 75% of cases were delta and 20% omicron

Dec. 23 — The lines intersect, with 50% of each variant

Jan. 1 — 84% of cases are omicron; 14% delta

Jan. 8 — 92% of cases in Mississippi are omicron

Jan. 24 — Numbers show new omicron cases have peaked in Mississippi and South Mississippi