TAMPA, Fla. (WFLA) — The U.S. Food and Drug Administration has now authorized a fourth COVID-19 vaccine for adults.

On Wednesday, the agency issued an emergency use authorization for the Novavax vaccine for adults.

The vaccine will be given in two doses and administered 21 days apart. However, the decision will now to go the Centers for Disease Control and Prevention and its advisory committee for recommendation on how the shots should be used.

The U.S. has already secured 3.2 million doses of the vaccine, according to the Biden Administration.

USF Health’s Dr. Michael Teng believes we need more vaccines, because we need a better way of vaccinating.

“If we’re going to have really effective vaccination, it’s always not the first generation that works, but the second generation vaccine,” Teng said. “The whole idea is to have a wide array of vaccines out there that everybody feels confident in.”

This latest vaccine comes as the BA.5 Omicron variant accounts for 65 percent of all COVID infections in the U.S.

The subvariant also makes up 66.5 percent of infections in the Southeast portion of the country, which includes Florida.

“You get progressively better at making a more effective vaccine over time,” Teng said. “Each generation of the vaccine gets better. It’s like software.”