The latest circulating COVID-19 variants have shown greater immune escape, which will likely lead to increasing cases over the coming months, experts said.
New Omicron subvariants BQ.1 and BQ.1.1 together now make up more than half of all COVID cases in the U.S. (30.9% and 31.9%, respectively), according to the , representing a rapid rise from early November when they represented about a quarter of all cases.
David Weber, MD, MPH, of the UNC Medical Center in Chapel Hill, North Carolina, said the rising prevalence of these variants is likely attributed to ineffective immune responses from prior infections and vaccination, but healthcare providers should still rely on tried-and-true approaches, such as boosters, antivirals, and masking.
"The bottom line is those variants, BQ.1 and BQ.1.1, because they escaped immunity from natural infection ... we'll expect to see increasing proportions of them over the next couple of months," Weber told .
"A that by December 1, [the variants] would be more than 50%, and they were correct," he added. "And they suggest by January 1, more than 80% of the circulating variants will be BQ.1 and BQ.1.1."
In response to the increasing prevalence of these variants, the this week that bebtelovimab, the monoclonal antibody found to be effective against earlier variants, would no longer be authorized for emergency use.
The FDA recommends that healthcare providers consider treatment options that are effective against these new variants, including ritonavir-nirmatrelvir (Paxlovid), remdesivir (Veklury), and molnupiravir (Lagevrio). The agency also highlighted the potential efficacy of bivalent COVID-19 boosters and the use of convalescent plasma for immunosuppressed patients.
Weber stressed that the best line of defense is the bivalent booster.
"Nothing is more important than a physician or a healthcare provider telling their patient, 'I strongly recommend this to you,'" Weber said. "That's really important because many people mistrust the medical environment, but they love their own provider, so it's really important for that medical provider to make a strong recommendation to get the bivalent vaccine."
The vaccine will be all the more important due to the uncertainty around BQ.1 and BQ.1.1, said Peter Katona, MD, of the UCLA Fielding School of Public Health in Los Angeles.
"We know that they're taking over," he told . "It's a question of what direction they take us. Are they going to take us into a more benign situation, are there going to be things that we only have to be careful about -- because of long COVID and because of the people who get really sick."
Katona noted that the long-term outlook on these variants is unknown at this point, so the focus is on treating patients with the options that are currently available and effective. Since the outlook for this winter is not clear, he emphasized the need to keep track of the local developments with these variants.
"It's a complicated mess," Katona said. "You have to look at where you are locally to kind of give you some guide."
The bigger picture, according to Weber, is the ongoing rate of cases and deaths from COVID, irrespective of the variant. He pointed out that COVID-19 is still the third leading cause of death in the U.S., so until the rates of cases and deaths can be brought down, we should continue to expect new variants to develop.
"Everybody who gets COVID is a little incubator for developing a more efficient virus," Weber warned. "And because millions of people continue to get COVID worldwide, and we've already been through the Alpha, Beta, Delta, Omicron, BA.1 [and] 2, and then BA.4 waves -- so we've had five or six waves of this going over 3 years -- I don't think there's anything particularly surprising that we're continuing to see new variants."