NEW HAVEN, Conn. (WTNH) — The COVID-19 omicron BA.5 variant now makes up for half of the new cases in the United States.

Doctors are seeing a lot more reinfections and explain why it’s still important to be vaccinated and boosted against COVID-19 so that your body has at least some defense.

“I do want to point out to people that if you’ve been vaccinated, if you’ve had a prior infection, if your immune system can recognize this virus, but the severity of illness is not as severe. So this isn’t starting from scratch. But it does explain why we’re seeing so many cases,” said Yale Medicine Physician F. Perry Wilson.

He said he gets a lot of questions about COVID-19 vaccine boosters.

Those ages five and older are eligible for one booster after two COVID vaccines. People 50 and up are eligible for two boosters after the first two COVID vaccines.

Dr. Wilson’s patients ask whether they should get their boosters now or wait for a possible new vaccine in the fall. He said not to wait for the fall because there are too many unknowns.

WEB EXTRA: F. Perry Wilson, a doctor and associate professor at Yale School of Medicine, discusses vaccines, BA.5 and monkeypox

“We do know that that third booster in particular for people who are younger than age 65 or so, is very protective for people over age 50 to 65 or older people, that fourth booster is very effective at preventing hospitalization and death. So I would say just get it.”

Wilson said to prepare to start hearing a lot more about monkeypox cases nationwide. Instead of all samples sent to the CDC for testing, labs nationwide will process them quickly.

People born before 1972 who got the smallpox vaccine may still have some protection from monkeypox.

“This was a very long-lasting vaccine. So some of the studies suggested even 20, 30 years out, that there were still detectable antibody levels. There may be some protection for those people,” Wilson said.

He also points out that people in that vaccinated group are now older with immune systems that may no longer be strong.