After a contentious meeting, vaccine advisers for the US Centers for Disease Control and Prevention (CDC) voted on Thursday to delay a vote on restricting hepatitis B vaccination for infants until Friday.
The meeting of the advisory committee on immunization practices (ACIP) turned confrontational at times before one member introduced a motion to delay the vote, which passed by six to three, to give advisers time to examine the wording before taking a vote.
In the unprecedented meeting, the vaccine advisers debated restricting access to the hepatitis B vaccine for infants – a significant step toward limiting safe and effective shots given for decades.
No new evidence on harms from the vaccine, which has been given to 1.4 billion people for more than three decades with a stellar safety record, was presented at the meeting. The shot is currently available at birth for all infants.
Two members demanded evidence of any harm from the vaccine while pointing to its benefits, while the vice-chair running the meeting at times interrupted their comments. Several of the advisers, who were all hand-picked by Donald Trump’s controversial health secretary, Robert F Kennedy Jr, are longtime anti-vaccine advocates.
The aborted vote on the hepatitis B shot, which is an extremely safe and very effective vaccine, follows previous meetings where advisers recommended restricting access to Covid vaccines and also measles, mumps and rubella and chickenpox vaccines – moves that made it more difficult for families and providers to understand their options.
Kennedy, a prominent anti-vaccine activist, has long pushed for delaying the shot. Experts say any change to the current hepatitis B vaccination recommended schedule could have significant and far-reaching consequences for childhood health in the US.
The leadership of the ACIP was shaken up earlier this week, with the previous chair, Martin Kulldorff, moving to the US Department of Health and Human Services (HHS).
The new chair is Kirk Milhoan, a pediatric cardiologist who has advocated against Covid vaccines and promoted the use of ivermectin, an anti-parasitic medication that is ineffective against Covid.
Recommending hepatitis B vaccination at birth has nearly eliminated transmission from birth parents and dramatically reduced cases of the illness in childhood. Infant immunization has been directly linked to a 99% decline in acute hepatitis B cases in children, adolescents and young adults between 1990 and 2019.
Simply holding discussions around established vaccines, without changing the recommendations, gives the impression that the science is not clear, said Debra Houry, who was chief medical officer of the CDC until this year.
“For parents, they’re going to be very confused,” Houry said. Families may wonder, if there is no new evidence that vaccines cause risk, why the advisers would consider changing the recommendation, she said. “They might question the whole vaccine schedule, or why things are done the way they are.”
Even short delays in giving children the hepatitis B vaccine have immense health and financial repercussions, according to a new model.
Delaying the shot from birth to two months, one of the potential votes for the committee, would lead to at least 1,400 infections, 300 cases of liver cancer, and 480 deaths every year – all preventable by vaccination, the researchers wrote. It would also result in more than $222m in additional healthcare costs every year.
A new review from the Vaccine Integrity Project of more than 400 studies over four decades found no evidence that delaying the vaccine would improve safety or effectiveness, and it found that vaccination at birth has no short- or long-term serious adverse events or deaths.
In September, the panel voted to change US vaccine policy and start recommending that children receive multiple vaccines to protect against measles, mumps and rubella and chickenpox, instead of a single vaccine that can protect against all four diseases. The following day, the panel voted to change Covid-19 vaccines to shared clinical decision-making – an opaque term not typically applied to routine vaccines.
The advisory panel can only make recommendations to the head of the CDC, acting director Jim O’Neill. The previous director, Susan Monarez, was ousted by the Trump administration in August after the White House claimed she was “not aligned” with the president’s agenda.
Childhood immunization rates continue to fall across the United States, amid a rise in vaccine hesitancy. In 2025, the US has faced its largest measles outbreak in three decades and risks losing its measles-eradication status.
Some of the presenters on Thursday made key misstatements about the hepatitis B vaccine, sparking heated debate.
Studies “generally found that the vaccine was safe and well-tolerated”, said Mark Blaxill, an author who has argued that vaccines cause autism and other conditions and who was recently named senior adviser at the CDC.
He pointed, however, to one study in which 18% of vaccine recipients reported minor side-effects like fatigue or weakness, diarrhea and irritability. “Those were dismissed as ‘well, the baby is just fussy’,” Blaxill said. “If you do compare those descriptions to definitions of encephalitis, those are possibly connected.”
“Irritability, fatigue, weakness, diarrhea, that is absolutely not encephalitis,” said Cody Meissner, a pediatrician and ACIP member, after Blaxill’s presentation. “That’s not a statement that a physician would make. They are not related to encephalitis and you can’t say that.
“There were so many statements that I don’t agree with that it’s hard to be succinct,” Meissner said in response to the presentations on the safety and effectiveness of the vaccine.
“This disease has gone down in the United States thanks to the effectiveness of our current immunization program,” Meissner said.
“In your opinion,” the vice-chair, Robert Malone said, interrupting him.
“Uhh, these are facts, Robert,” Meissner responded.
When Malone interrupted again, asking what his question was, Meissner responded: “I am asking you what is the risk of a hepatitis B vaccine in neonates?”
Joseph Hibbeln, an ACIP member and psychiatrist and neuroscientist, took up the same line of inquiry: “Is there any specific evidence of harm of giving this vaccination before 30 days? Or is this speculation?”
“There is limited evidence about the long-term risk,” Blaxill responded.
“So this was speculation and limited evidence. OK, got it,” Hibbeln said.
“We have documented through the compensation program, and we also have it documented on the package,” Malone said.
“No, Robert,” Meissner interjected. “I was chair of the vaccine injury compensation program for two years, and I can absolutely tell you that these are not confirmed associations.”
Outside experts also voiced concerns about the discussion.
“The data presented are far from complete as far as the full picture of disease burden and safety,” said Jane Seward, a retired CDC vaccine policy expert. “The ‘CDC’ presenters are not subject matter experts. No CDC experts have been invited to present or join working group discussions.”
The US population is very diverse and its healthcare system does not provide universal healthcare coverage, creating challenges to testing and follow-up vaccination for hepatitis B, Seward said.
“Babies will be missed. Some will acquire a serious chronic infection that may result in liver damage or cancer.”
