Booster shots of the Covid-19 vaccines already in use are enough to combat the fast-spreading omicron variant, Dr. Anthony Fauci, the president's chief medical adviser, said Wednesday at 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, the omicron variant has been detected in at least 36 states. It currently accounts for 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 two days. In comparison, cases of the delta variant appear to double every two weeks.
While vaccine manufacturers have said they are looking into developing shots targeting omicron, Fauci suggested that may not be necessary.
During Wednesday's briefing, Fauci cited lab data showing that a third dose of Moderna's Covid-19 vaccine increases the shots' ability to neutralize the omicron variant by a "substantial degree." That research, he said, will be available to the public in the coming days or weeks.
Last week, Pfizer and its partner BioNTech said that their analysis of blood samples in a lab showed a third dose of their Covid vaccine offered strong protection against the omicron variant.
Despite the promising data, outside experts said it is critical for drug companies to continue researching reformulated vaccines in case new shots are needed as the virus mutates.
"If it's not omicron, it's another variant," said Dr. Jesse Goodman, a professor of medicine and infectious diseases at Georgetown University Medical Center, as well as a former chief scientist with the Food and Drug Administration.
"We need to understand how to make vaccines that are going to be more protective against really diverse variants," he said.
Vaccine manufacturers are indeed attempting to stay ahead of any new variants that may emerge.
"We are continuing to advance the research and development of a variant-specific vaccine in the event that it is ever needed," Jerica Pitts, a spokesperson for Pfizer, wrote in an email.
For now, current boosters are likely enough to derail the projected onslaught of omicron, Fauci said.
"If you're eligible 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.