A panel of vaccine advisers to the federal government – now embroiled in controversy under the leadership of Health Secretary Robert F. Kennedy Jr – kicked off a two-day meeting with a debate over proposed changes to the childhood vaccine schedule.
In years past, the gathering of the Advisory Committee on Immunization Practices, or ACIP, would typically draw little interest from the broader public, but the panel that provides guidance to the Centers for Disease Control and Prevention on how vaccines should be used has come under intense scrutiny as of late.
This is the group's second meeting since Kennedy Jr. scrapped the existing panel of experts installed under the Biden administration and replaced them with an entirely new roster, including five members he added just this week.
The meeting began with pointed comments from Martin Kulldorff, an epidemiologist who is serving as the committee chair, against critics –– among them a slate of former CDC directors who have said the new members, selected by Secretary Kennedy, are "unqualified" and "share his dangerous and unscientific views. "
Kulldorf rebuffed the idea that he or others on the panel were "anti-vaxxers" and challenged the former directors to an "open public debate."
"If they want to be trusted, they should all accept," he said, "The fact is we are honest vaccine scientists that let the data speak, whether the results go in one direction or the other."
The panel devoted the morning to a discussion of whether to overhaul existing CDC recommendations that allow children under age 4 to receive a combination shot for measles, mumps, rubella and chickenpox (or varicella), the MMRV vaccine.
The vast majority of children in the U.S. – about 85% – get separate shots for MMR and chickenpox, though parents currently have the option to give their children the single shot to cover all four diseases.
CDC staff presented evidence showing a slightly increased risk of fever-related seizures in children ages 12-23 months associated with the MMRV shot compared to the MMR, which concerned some committee members.
"I would go with the option that seems to be safer," said ACIP member Retsef Levi, an MIT professor of operations management who gained prominence during the pandemic for criticizing COVID vaccines.
But several physicians on the panel and representatives from major medical associations in attendance balked at the proposal.
Dr. Cody Meissner, a pediatrician and professor at Dartmouth College and ACIP member, said while "frightening" for the family, these fever-related seizures are not uncommon, occurring in 3 to 5% of all children.
"Every pediatrician is experienced in febrile seizures. We know that the prognosis is excellent," he said.
Removing the MMRV shots from the vaccine schedule for children under age 4 would spark more public confusion, compromise insurance coverage and potentially lead to fewer kids being vaccinated, said Dr. Jason Goldman, president of the American College of Physicians who is acting as a liaison to the committee.
While most children get the chickenpox vaccine as a separate shot, some parents might prefer to reduce the number of jabs, even if the combination carries some risk.
"I urge this committee not to change the recommendations if they truly want to give the power to the parents to decide what is best for their child," he said.
Meissner said of the recommendation against the combination vaccine: "What we're saying is we don't trust parents," adding "I prefer that families have the option to make the selection."
The panel's recommendations determine which shots are offered for free through the Vaccines for Children program. They also influence what many health insurers must cover.
The meeting comes on the heels of a contentious Senate hearing on Wednesday with the recently-ousted CDC director Susan Monarez.
Monarez testified that she was fired after clashing with Kennedy over his demands that she preemptively agree to approve vaccine recommendations from ACIP, and fire career scientists.
"He said the childhood vaccine schedule would be changing starting in September and that I needed to be on board with it," Monarez said.
In his remarks, Kulldorf criticized Monarez and several other high-level CDC officials who recently resigned in protest of changes at the agency, saying they had not reached out to him, despite their concerns about the committee.
The absence of a liaison from the American Academy of Pediatrics – the leading national group representing pediatricians in the U.S. that would usually collaborate with the panel – was another sign of the increasingly polarized nature of vaccine policymaking.
The AAP had decided to boycott the meetings, arguing federal vaccine policymaking is no longer a "credible process." Kennedy has barred professional medical groups such as the AAP from serving in their traditional roles as expert liaisons to workgroups of the advisory committee.
Meissner said the AAP was making a "grave mistake not to participate" and "moving itself to irrelevance."
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