Health and Human Services Secretary Robert F. Kennedy Jr.'s campaign to remake how doctors use vaccines recently took a big legal hit. A federal judge in Boston blocked, at least temporarily, Kennedy's cut to federally backed childhood vaccines, along with Kennedy's other controversial new vaccine policies.
The decision came as Kennedy was publicly focusing more on nutrition because of White House trepidation his unpopular vaccine restrictions might hurt Republicans politically. As a result, uncertainty about the Trump administration's already tumultuous federal vaccine policies has only intensified, as questions swirl about how the administration will respond to the legal setback.
One step Kennedy could take involves a shot babies get to protect them against respiratory syncytial virus. RSV is highly contagious and can be very dangerous for babies. In fact, RSV is the most common reason babies end up in the hospital in their first year of life.
"Some of these children are sometimes on ventilators. And they can be on oxygen because they really can't breathe with this virus," says Dr. Yvonne Maldonado, a pediatric infectious disease specialist at Stanford University. "So it's quite severe in the very young. Some of these babies develop chronic lung disease from this infection and can develop asthma."
But two new shots have been a game changer for protecting babies against RSV, she says. These laboratory-made "monoclonal antibodies" fight infections like natural antibodies. More than half of U.S. infants have gotten one of the shots, according to a Centers for Disease Control and Prevention survey in February. The shots are about 80% effective at preventing babies from ending up in intensive care because of RSV, the CDC says.
"They're very new but they've already had great success. The monoclonal antibodies have resulted in major reductions in hospitalizations for babies for RSV infections," Maldonado says. "It's pretty remarkable."
So Maldonado and other infectious disease experts were surprised and alarmed when the Food and Drug Administration announced a review of the safety of these monoclonal antibodies in December.
"These products were already thoroughly reviewed for safety, including by the FDA. The science and the facts will bear out that these are very safe products," says Dr. Sean O'Leary, an assistant professor of pediatrics at the University of Colorado who chairs the American Academy of Pediatrics's infectious disease committee.
O'Leary suspects the investigation could be another example of Kennedy trying to undermine immunizations.
"It's more of the same. It's falsely promoting these safety risks that aren't real in the name of continuing to try to dismantle the U.S. vaccination program," O'Leary says.
The FDA has not said when its review might be complete.
Others welcome the review, pointing to adverse reactions that have been reported among babies who got the shots, including fevers, seizures and even some deaths.
"I am concerned about the safety of these products," says Brian Hooker, chief medical officer for the Children's Health Defense, a group that is critical of vaccine safety and mandates. "I think the entire safety profile, especially for this very vulnerable population, is worth taking a look at."
The companies that make the shots, Sanofi and Merck say they're cooperating with the FDA's review. They stress that the shots are very safe and there's no evidence the deaths or any of the other serious reactions after vaccination were caused by the shots.
"As a father myself and as someone who leads our medical affairs group, the death of any child is a tragedy," says Ayman Chit, who leads Sanofi's medical affairs department for North America. "But no deaths during our clinical studies were linked to the immunization. And this is not only our conclusion, the FDA itself in analyzing all of our data has come to the same conclusion."
Nevertheless, many public health experts worry the FDA's safety review could lead to restrictions that make it harder for babies to get the shots and discourage doctors or parents from protecting babies from RSV.
"I think it would be such a terrible shame if infants in the United States no longer had protection from RSV," said Dr. Paula Annunziata, senior vice president, infectious diseases and vaccines at Merck. "I think that would be horrible."
Beyond RSV, another move that could have a chilling effect on vaccination would involve significantly expanding the conditions that would be eligible for compensation through the federal Vaccine Injury Compensation Program, which compensates families for complications associated with vaccines.
Vaccine supporters worry that change could threaten the solvency of the program, which is vital for maintaining the viability of the vaccine market by limiting legal liability of manufacturers. Aaron Siri, an attorney who has challenged vaccine mandates and sued over vaccine injuries, is close to Kennedy and just petitioned him to add more than 300 conditions that could qualify for compensation.
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