Booster shots of the COVID-19 vaccines already in use are enough to combat the fast-spreading omicron variant, Dr. Anthony Fauci, chief medical adviser to President Joe Biden, said Wednesday during a media briefing.
That is, it is unlikely the shots will need to be reformulated to target omicron specifically.
"Our booster vaccine regimens work against omicron. At this point, there is no need for a variant-specific booster," Fauci, also the director of the National Institute of Allergy and Infectious Diseases, said.
While the delta variant still accounts for the vast majority of COVID-19 cases in the country, omicron is now being detected in about 3 percent of new cases, according to the Centers for Disease Control and Prevention.
In some states, it's even higher, CDC director Dr. Rochelle Walensky said during the briefing. The agency projects that omicron could account for 13 percent of new cases in New Jersey and New York.
The proportion of omicron cases is expected to grow in the coming weeks, Walensky said, adding that the number of new omicron cases doubles about every 2 days.
The omicron variant has been detected in at least 36 states.
"If you're elibible for a booster shot, it's critical that you get boosted today," Jeff Zients, the White House Covid-19 response coordinator, said during the briefing. "Don't wait."
Everyone ages 16 and up is now eligible for a booster dose.
Less than a third — 27.2 percent — of the U.S. population able to get a booster has done so, the CDC said.
This article was originally published on NBCNews.com.