TAMPA, Fla. (WFLA) — The CDC says people who are severely immunocompromised can get a fourth COVID-19 vaccine shot as early as this week.

Moderna and Pfizer also say they’re working on an Omicron variant vaccine that could roll out in a few months, but there are questions about the fourth dose for everyone.

The CDC says Omicron is now 98% of new COVID-19 infections in the U.S. Dr. Michael Teng with USF Health doesn’t believe the public health agency will recommend a new booster so soon.

“That’s a little bit too much, because how many times are you going to boost, over activating your immune system is not great either,” Teng said.

The CDC says more than 200 million people are fully vaccinated, which is two Pfizer or Moderna shots, or the one dose Johnson & Johnson shot, and more than 76-million people have a booster.

Dr. Teng says if the next variant is derived from Omicron then an Omicron booster is important going forward, but until that happens, you shouldn’t worry about getting the fourth shot anytime soon.

“We’re not at a point where we need to change the vaccine strain,” Teng said.

The CDC adds the increases in cases and hospitalizations will stress the healthcare system in the coming weeks.

Pfizer’s CEO says he doesn’t know if we’ll need it, or how they’ll use it, but they will have the new vaccine ready in March.