New Covid vaccines from Pfizer, Moderna and Novavax will likely protect against Eris variant
A pharmacist prepares to administer Covid-19 vaccine booster shots during an event hosted by the Chicago Department of Public Health at the Southwest Senior Center in Chicago, Illinois, Sept. 9, 2022.

New Covid vaccines from Pfizer , Moderna and Novavax will likely provide protection against the new "Eris" variant, now the dominant strain of the virus in the U.S.

The drugmakers designed their updated vaccines to target the omicron subvariant XBB.1.5, which is slowly declining nationwide. But health experts and initial data suggest that the new shots will still be effective against Eris, or EG.5, and other widely circulating variants – all of which are descendants of omicron.

"I think that these vaccines will provide very substantial protection against EG.5. Maybe just a little bit of loss, but it's nothing that I'm very concerned about," Dr. Mark Mulligan, director of the NYU Langone Vaccine Center, told CNBC. "It looks like we're going to be OK."

All three companies are still waiting for the Food and Drug Administration to approve their vaccines, meaning those jabs won't be available to the public for a month or so. The Centers for Disease Control and Prevention also has to decide which Americans should get the shots and how often.

Still, the upcoming arrival of those vaccines offers some reassurance to Americans as Eris and other Covid variants fuel a slight uptick in cases and hospitalizations across the country but remain below the summer peak that strained hospitals this time last year.

Eris accounted for 17.3% of all cases in the U.S. as of earlier this month, according to the latest data from the CDC. The new strain surpassed XBB.1.5, which accounted for roughly 10% of all cases.

The World Health Organization earlier this month designated Eris a "variant of interest," meaning it will be monitored for mutations that could potentially make it more severe.

But the health agency and experts said Eris does not appear to pose a significant threat – or at least no more than any of the other omicron variants currently circulating in the U.S. It's also not expected to cause a huge wave of Covid cases like other strains have in previous years.