CDC Slashes Omicron Estimates: See Latest Connecticut Cases

CONNECTICUT — Federal health officials have walked back week-old estimates claiming the highly contagious omicron variant is responsible for nearly 3 out of 4 new coronavirus cases in parts of the United States, including in the Northeast.

On Dec. 18, the Centers for Disease Control and Prevention reported that 73 percent of new cases were linked to omicron. This week, however, the agency revised those figures, slashing the earlier estimate to 23 percent — a drop of nearly 50 percentage points.

The drastic change suggests that while omicron cases are on the rise, the variant is not infecting people at the rate the CDC had projected.

"There's no way around it, it is a huge swing that makes it seem like something went really wrong," Dr. Shruti Gohil, associate medical director at UC Irvine's School of Medicine, told National Public Radio. "But there is always a delay in the testing information that comes in, and that's what the public should take away."

The new data comes a month after omicron was detected half a world away and days after Americans gathered for the holidays.

Despite this week's revision, omicron cases are increasing nationwide. The variant accounted for nearly 59 percent of all new cases for the week ending on Dec. 25. The delta variant — the variant more likely to cause severe illness — still accounts for nearly 41 percent of new cases.

In the Northeast, delta cases outpace omicron, according to the federal Centers for Disease Control and Prevention. The delta variant is responsible for 55.3 percent of all COVID-19 cases in Connecticut, Rhode Island, Maine, Massachusetts, New Hampshire and Vermont. Omicron triggered 44.5 percent, and other variants, or the original coronavirus, is responsible for 0.2 percent of the cases.

In some regions of the country, the spike in omicron cases is significantly higher than the national average. The variant accounts for more than 88 percent of new infections in New York and New Jersey, and nearly 87 percent in the Texas region.

The delta variant had been dominant since June, and as recently as the end of November represented 99.5 percent of new cases.

Only about 33 percent of Americans have gotten their COVID-19 booster shots, which health officials say is the best defense against the omicron variant. About 62 percent of Americans are fully vaccinated but aren’t boosted, and health officials are worried about the nation’s ability to withstand a fifth wave of COVID-19.

For more information, go to the CDC data tracker.