The Centers for Disease Control and Prevention updated its model of COVID-19 variant breakdown dramatically on Wednesday, predicting that the Omicron variant was responsible for around 59% of cases in the United States as of Dec. 25.
The CDC trimmed down its proportion of cases for the new variant for the week ending Dec. 18 to 22% from 73%, citing additional data and Omicron's fast rate of transmission, which led to the disparity.
The CDC stated that the discrepancy was the result of the rapid spread of the highly transmissible Omicron.
The variant was originally found in November in southern Africa and Hong Kong, with the first case in the United States being reported on Dec. 1 in a fully inoculated individual who flew from South Africa.
A CDC representative stated that new data from that time period had arrived, and there was a lower proportion of Omicron.
Given the estimating process, experts said they were "not surprised" by the CDC's new guidelines, but felt the agency did a "miserable job" of explaining the uncertainty of it all, according to The New York Times.
A virologist, David O'Connor, is of the opinion that this is one instance among many where researchers and medical experts are attempting to project "an air of confidence" about what's going to unfold.
The CDC's revised Dec. 25 model has a smaller confidence range for Omicron prevalence: 41 to 74%. Based on the agency's current estimate, the Delta strain still accounts for 41% of infections in the U.S.. The model is updated weekly by the agency.
Since Omicron's discovery, the variant has rapidly spread around the world, causing significant travel cancellations and dashed hopes for a more normal holiday season.
Former FDA Commissioner Scott Gottlieb noted on Twitter that if the CDC's new estimate of Omicron prevalence is accurate, it shows that Delta infections are still responsible for a significant share of current hospitalizations.
The FDA disclosed that the data includes estimates that may be different from projections taken at later timeframes.
As of Dec. 25, the Delta variant, which had been the prevalent strain in recent months, accounted for 41% of all COVID-19 cases in the U.S., CDC statistics showed.
More than 206,000 daily COVID-19 infections are already being recorded in the U.S., and the number is constantly increasing.
Currently, the U.S. records more than 206,000 daily COVID-19 infections - a number that is rapidly increasing. More than 2 million people flew Tuesday, according to Transportation Security Administration data.
