Health and Human Services Secretary Robert F. Kennedy Jr. shocked many when he announced all 17 sitting members of the Centers for Disease Control and Prevention’s independent vaccine advisory committee would be removed.

In an op-ed for The Wall Street Journal, Kennedy said the Advisory Committee on Immunization Practices (ACIP) was plagued by conflicts of interest and was a “rubber stamp” for all vaccines.

The U.S. Food and Drug Administration is the agency that authorizes or approves vaccines. The ACIP holds public hearings and then has non-binding votes on potential recommendations, and the CDC director finalizes the recommendations.

Currently the CDC director role remains vacant and Kennedy has been making the final recommendations.

Kennedy told ABC News on Tuesday that the replacements for ACIP will not be “anti-vaxxers” and that he intends to replace the panel by the end of the month.

“We’re going to be bringing people onto the ACIP panel — not anti-vaxxers — we’re bringing people on who are credentialed scientists, who are highly credentialed physicians, who are going to do evidence-based medicine, who are going to be objective and who are going to follow the science and make critical public health determinations for our children based upon the best science,” Kennedy said.

But Kennedy also suggested that current list of vaccines that are recommended for children would be re-analyzed by the new ACIP members, because he doesn’t trust the science that led to their initial approvals.

A number of public health experts and vaccinologists told ABC News that they are concerned new committee members could lead to changes in which vaccines are no longer covered by public and private insurers, and that committee seats may now be filled by vaccine skeptics without scientific knowledge to evaluate the recommendations.

“I think it’s disingenuous. I don’t think this has anything to do with conflict of interest,” Dr. Peter Hotez, a professor of pediatrics and molecular virology at Baylor College of Medicine in Houston, who has helped develop several vaccines, told ABC News. “I think he either wants to get rid of ACIP altogether or stack it with his with people that believe in his … pseudoscience.”

Who will the new members of the committee be?

The ACIP is comprised of up to 19 voting members, six ex officio members representing other federal agencies and 30 non-voting representatives of liaison organizations such as the American Academy of Pediatrics and the American Medical Association.

The panel develops recommendations on the use of vaccines in the U.S including timing and dosage or if there are situations in which a vaccine should not be used.

According to the CDC, ACIP makes recommendations on incorporating licensed new vaccines into the current immunization schedule as well as recommendations on vaccine formulations. It also reviews older vaccines to consider revising its recommendations.

The CDC sets immunization schedules for adults and children based on ACIP recommendations.

The members removed by Kennedy include experts in pediatrics, infectious diseases, global public health, epidemiology and family medicine.

Among them was Dr. Noel Brewer, a professor in the department of health behavior at the University of North Carolina Gillings School of Global Public Health.

According to his biography page on the school’s website, he has been a co-author in the publication of more than 375 papers examining vaccination, tobacco use, medical screening and other cancer-related health behaviors.

Brewer told ABC News Live he and his colleagues did not see the purge coming and said he learned of it from journalists contacting him and asking if he saw Kennedy’s op-ed in The Wall Street Journal.

He said that ACIP has one of the strictest set of rules around conflict-of-interest of any committee he’s been part of and there’s no evidence of members voting in favor of products because of personal, or business, interests.

“They work really hard to make sure that we don’t have the conflicts of interest,” Brewer said. “So, I can’t accept any money from a drug company. I cannot accept any sort of funding from them. I can’t be part of a lawsuit against a drug company. None of that stuff is possible.”

The CDC has published a list of conflicts of interest declarations disclosed by voting members during public meetings since 2000, which was most recently updated in early March.

Dr. Dorit Reiss, a professor of law at the University of California College of the Law, San Francisco — whose research focuses on legal and policy issues related to vaccines — told ABC News very few members of the committee have conflicts of interest, and those who do announce them at the beginning of the meeting and don’t vote on those issues.

Brewer said he assumes Kennedy’s new nominations will “have the same level of vaccine skepticism as the current secretary, but it’s hard to know, and I’m just hoping for the best.”

In a statement, HHS spokesperson Andrew Nixon told ABC News, “Secretary Kennedy is committed to restoring public trust in vaccine policy by ensuring that advisory panels like ACIP are guided by independent, gold standard science — free from conflicts of interest and ideology.”

Dr. Gregory Poland, a vaccinologist and president and co-director of the Atria Research Institute — who previously served two terms on the ACIP and then two terms as a liaison — told ABC News there’s only speculation as to whom Kennedy will select because no names have been announced.

However, he added he doesn’t have concerns as long as the new members bring “some domain of expertise” and “adhere to the rigor of the scientific method.”

“Presumably, the criteria will be around a concept that the administration has announced called ‘Gold Standard Science,'” Poland said, referring to Trump’s executive order in late May that seeks to promote the standard through replication, transparency, unbiased peer review and without conflicts of interest.

“I think a definition of ‘gold standard science’ is appropriate. We know what that means in the scientific field, and then if you array experts who adhere to gold standard science, that’s a good thing,” he continued.

Reiss said the timing of Kennedy’s announcement comes just prior to an upcoming ACIP meeting scheduled to be held between June 25 and June 27 to discuss new recommendations for several vaccines, including the HPV vaccine and the COVID-19 vaccine.

“That’s a really short time for vetting members, which usually takes months,” she told ABC News. “The first question is: is Kennedy going to try to quickly put in a range of names, which would suggest that he either has been preparing a roster for a long time, or is he going to do it really quickly?”

Could any changes be coming to vaccine recommendations?

Reiss said if the new ACIP members make any changes to vaccine recommendations, it could lead to changes related to insurance coverage.

Private insurance providers are required under the Affordable Care Act to cover ACIP recommendations, but not required to cover others, she said.

Additionally, the federal Vaccine for Children program, which provides vaccines to children whose parents or guardians may not be able to afford them, automatically covers vaccines recommended by ACIP and approved by the CDC.

For adults, Medicare covers costs of ACIP-recommended vaccines for patients with Part D plans, and state Medicaid agencies are required to cover costs for most beneficiaries receiving ACIP-recommended vaccinations.

If ACIP no longer recommends certain vaccines, federal programs may not be required to cover costs for adults or children.

“It could dramatically affect access, because people might not be able to cover childhood routine vaccines, which means that people who want to vaccinate their children won’t be able to and it could affect the willingness of providers to give them,” Reiss said.

Reiss said ACIP changing recommendations for vaccines could also affect the National Vaccine Injury Compensation Program, which provides compensation for vaccine injuries if the CDC recommends the category of vaccine for routine administration to children or pregnant women.

ABC News’ Youri Benadjaoud and Cheyenne Haslett contributed to this report.