RALEIGH, N.C. (WNCN) – These ongoing conversations about boosters for each of the vaccines are causing some confusion among the public. It’s left some people wondering why the science about how many doses we need has changed.

When COVID-19 shots first came online, vaccine makers laid out either a one or two-dose regimen. Now, those vaccine makers say everyone needs an extra jab in the arm.

Meanwhile, the FDA and CDC say just some groups do.

“I think sometimes it’s perceived that this makes us confused when in reality, it’s just we’re getting more information “

Dr. Tony Moody, a physician scientist at Duke Health, said this is how science works. It’s one of the few times we’ve seen science play out in public.

“Usually when we can say ‘Here is the answer’, it’s because we have 50 years of science behind us and all those arguments have already happened,” Moody said.

He said the current conversations on boosters are a glass half empty versus half full philosophy.

“It comes down to are you looking at it from a public health perspective or are you looking at it from a perspective of what do I do with an individual patient sitting in front of me,” said Moody.

He and UNC School of Medicine professor of epidemiology Dr. David Weber think of boosters in terms of car safety.

“Airbags alone work. Seatbelts alone work most of the time but together they work better,” said Weber.

For now, they want to focus on people who don’t even have one shot in the arm.

“That’s going to be a better investment,” said Moody.

“That’s the most important thing we can do is convince those that are vaccine-hesitant or resistant that the vaccine are safe. They’re effective,” said Weber.

He wants to ensure everyone has some kind of basic protection.

“Really the issue is for the unvaccinated people. They need to go out and get their vaccine,” Weber said.