Fauci: Early data show omicron not as severe as delta for the vaccinated

Early data show the omicron variant of the coronavirus appears to be less severe than the delta strain among people who are vaccinated, Anthony Fauci said Wednesday.

Citing international studies and some initial data from U.S. hospitals, Fauci said people who are vaccinated and boosted are also less likely to be hospitalized. And despite a surge in infections over the past month, hospitalizations have not increased nearly as quickly.

“We know now, incontrovertibly, that this is a highly, highly transmissible virus. We know that from the numbers we’re seeing,” Fauci told reporters during a White House briefing.

But, “all indications point to a lesser severity of omicron versus delta,” he said. 

Omicron is now the dominant strain of coronavirus, but delta is still prominent. Cases were already rising steadily this fall because of the delta variant, but the emergence of omicron in the past month has led to a near vertical spike.

The U.S. on Tuesday broke a record for most single-day COVID-19 infections, with 441,278 cases. That surpassed the previous daily record by close to 150,000.

On Wednesday, the Centers for Disease Control and Prevention reported another 431,567 infections. The seven-day average of cases hit a record 277,241, an increase of more than 60 percent over the past week. 

There are still around 1,100 people dying from COVID-19 every day, but it’s a far cry from last January’s peak average of about 3,300, before vaccines were widely available. 

According to the CDC, the omicron variant accounted for about 59 percent of all U.S. infections as of Dec. 25. So while a majority of new infections are attributed to omicron, the delta variant still accounts for about 41 percent of infections. 

“[I]f CDC’s new estimate of Omicron prevalence is precise then it suggests that a good portion of the current hospitalizations we’re seeing from Covid may still be driven by Delta infections,” former Food and Drug Administration commissioner Scott Gottlieb tweeted on Tuesday. 

But there are some promising signs. Fauci on Wednesday said there’s been a 126 percent increase in cases over the past two weeks, but only an 11 percent increase in hospitalizations.

While hospitalizations and deaths are a lagging indicator, the “disparity between cases and hospitalizations strongly suggest there will be a lower hospitalization to case ratio,” Fauci said.

Fauci noted that omicron has some ability to evade immunity, particularly against infection. But for people who are vaccinated, they remain protected against severe illness.

“Importantly, and the bottom line message here, boosters bring back up that degree of protection to a level that is approximately what it was before. So boosters are critical in getting our approach to omicron to be optimal,” Fauci said.

He cited a study from the UK, which found people infected with omicron are 60 percent less likely to need emergency care compared to people infected with delta, and 40 percent less likely to be admitted to the hospital compared to those infected with delta.

When asked about the percentage of vaccinated people in the hospital with COVID-19, CDC Director Rochelle Walensky said Wednesday it was much worse for the unvaccinated.

“What I can tell you is that compared to people who are boosted, if you are unvaccinated, you are 10 times more likely to be a case and 20 times more likely to be a fatality. Compared to people who are [vaccinated], you are 17 times more likely to be in the hospital,” Walensky said.

Still, Fauci cautioned Americans not to be complacent, because hospital systems are still overwhelmed in certain areas of the country. 

An extremely high volume of cases may override some of the impact of the lower disease severity, he said. 

He also acknowledged that children are getting infected with omicron, including some who are too young to be vaccinated. 

According to data from the CDC and Department of Health and Human Services, an average of 334 children have been admitted to the hospital with COVID-19 daily for the week that ended Dec. 27.

“More children are being infected with the highly transmissible virus and with that, there naturally will be more hospitalizations in children,” Fauci said, but added that many children hospitalized with COVID-19 were admitted for other reasons, not because of COVID-19.

“The final conclusion about the level of severity in children remains to be determined,” Fauci said.