Covid vaccines targeting Omicron should be standard, panel says

At Thursday’s committee meeting, advisers debated how often to offer injections, which variants to defend against and whether vaccines were supposed to stop only hospitalizations or infections.

Some experts said it was too early to tell if annual doses were needed, as is the case with the flu.

“I think we need to see what’s happening with the disease burden,” said Dr. Cody Meissner, director of pediatric infectious diseases at Tufts University School of Medicine. “We may or may not need an annual vaccination. It’s just terribly early, it seems to me, in the process of answering that question.

Several new studies in recent days have reported results that, although riddled with data gaps and other uncertainties, their authors say, reinforce the benefits of updated bivalent booster injections. These vaccines were designed to defend against both the original version of the virus and the BA.5 Omicron subvariant that spread to the United States in the fall.

One of them, published in the New England Journal of Medicine, found that the bivalent boosters generated stronger protection than the original booster formulations.

The so-called bivalent booster was around 62% effective against severe Covid, the study found, compared to the original booster, which was 25% effective. (The study looked at the original recall last summer and the updated recall in the fall.)

Another study, conducted by the Centers for Disease Control and Prevention, suggested that the updated booster worked equally well against the new Omicron subvariant, XBB.1.5, as against the previous version of Omicron, BA. 5. For adults under 50, a bivalent booster was 48% effective against Covid infections caused by XBB.1.5, according to the CDC, and 52% effective against infections caused by BA.5.