RALEIGH, N.C. (WNCN) — Researchers want to know if four doses of the mRNA COVID-19 vaccines work even better than three.

A hospital in Israel is studying the safety and effectiveness of a second booster dose for some medical workers who got their last shot at least four months ago.

One of the key concerns raised by the fourth-dose concept — that it might cause more harm than good by wearing out the immune system — shouldn’t be much of a concern at all, local doctors say.

“That sounds like a little bit of snake oil to me. I’ll be totally honest,” said Dr. Cameron Wolfe, an infectious disease expert at the Duke University School of Medicine. “I don’t see any reason why that would bear out.”

Added Dr. Cynthia Gay, an assistant professor of medicine in the division of infectious diseases at the University of North Carolina Chapel Hill School of Medicine: “There’s really no reason why the immune system would become fatigued or not be able to respond.”

The flu shot everyone is supposed to get every year doesn’t seem to overload anyone’s immune system, Wolfe said.

A more important question is the timing of the booster.

“You probably don’t get the same bang for the buck with giving a booster too early, for example, or giving one when it’s not needed,” Gay said.

Israel, which is conducting the study, is a leader in the vaccination effort and started giving COVID boosters vaccines in July — months before they were administered in the United States.

“I think that has led them into a trap, actually, here for omicron because you’ve suddenly now got a wave arriving when they’ve been boosted,” Wolfe said. “And so their question now is, if we want to keep patients out of the hospital in Israel, do we need to top them up again because of omicron.”

That’s why Gay called the idea of a fourth shot in the U.S. “a little premature.”

Dr. Anthony Fauci said it’s “conceivable” that a second booster could be called for.

“But right now we are hoping that we will get a greater degree of durability of protection from that booster shot,” he said.

Here in North Carolina, 67 percent of people who can get a COVID vaccine — those 5 and older — have gotten at least one dose while 62 percent are fully vaccinated. Of those eligible for a booster, only a little over half have gotten one.

“Frankly, we need to focus on getting people their first booster,” Wolfe said.

The messaging around boosters in the U.S. has been inconsistent at best.

How should we fix that?

“I think what’s hard for people to understand because there’s just so much information where we’re just sort of being bombarded with it in a way,” Gay said. “But that’s a good thing and a bad thing in the sense that when we’re not able to sort of distill it, sit with it, and then have consistent messaging across countries and across different groups who are who are advising on this. I think that’s where the inconsistency comes in. 

“We are getting new information about COVID and the vaccines and the waning immunity and other treatments all the time,” she added. “It becomes difficult for even, I think, clinicians who, this is our job is to try to keep up with this information. It is difficult. … Where we can learn is to try to be more transparent about what the new information is.”

CBS 17’s Joedy McCreary has been tracking COVID-19 figures since March 2020, compiling data from federal, state, and local sources to deliver a clear snapshot of what the coronavirus situation looks like now and what it could look like in the future.