The Centers for Disease Control and Prevention has drastically reduced its estimate of Omicron cases in the US, saying the variant accounted for about 59 percent of COVID-19 infections as of Christmas Day xe2x80x94 a massive drop from the 73 percent previously reported.

The CDC also significantly lowered its estimate for the week before Christmas, saying that the variant accounted for just 22.5 percent of all infections as of Dec. 18. The public health agency previously estimated that Omicron accounted for 73.2 percent of cases that week.

This could mean that the Delta strain could actually be behind many of the current COVID-19 hospitalizations, former FDA chief Scott Gottlieb said.

xe2x80x9cSetting aside the question of how the initial estimate was so inaccurate, if CDCxe2x80x99s new estimate of #Omicron prevalence is precise then it suggests that a good portion of the current hospitalizations wexe2x80x99re seeing from Covid may still be driven by Delta infections,xe2x80x9d Gottlieb wrote on Twitter.

The CDC blamed the disparity on the rate with which the highly transmissible variant spreads.

xe2x80x9cThere was a wide predictive interval posted in last weekxe2x80x99s chart, in part because of the speed at which Omicron was increasing,xe2x80x9d CDC rep Jasmine Reed told Politico. xe2x80x9cWe had more data come in from that timeframe and there was a reduced proportion of Omicron.xe2x80x9d

The revised Christmas model includes a narrower confidence range of Omicronxe2x80x99s prevalence: 41.5 to 74 percent. The new model suggests that Delta still accounts for 41.1 percent of infections across the country.

Tuesdayxe2x80x99s revision came as the US logged its highest single-day total of new COVID-19 cases xe2x80x94 with 441,278 infections passing the previous daily record by nearly 150,000 cases, according to the report.

Reed also said the daily case total is likely an xe2x80x9coverestimatexe2x80x9d due to lagging state reporting. Many testing centers were closed over the holiday weekend.
xe2x80x9cThe counts of cases will become more stable after the new year,xe2x80x9d she told Politico.

Meanwhile, former US Surgeon General Jerome Adams criticized the CDC for its decision to cut isolation periods from 10 days to five.
xe2x80x9cI love the CDC. Grew up wanting to work there and have been one of their most ardent defenders. I never dreamed the day would come when I would advise people NOT to follow their guidance,xe2x80x9d he said in a tweet.

xe2x80x9cThey wouldnxe2x80x99t even follow it for their own family,xe2x80x9d he added.