RFK, Jr., Questions Safety of Approved RSV Shots for Babies

FDA officials are newly scrutinizing several approved therapies to treat RSV in babies despite the fact that these shots were shown to be safe in clinical trials

By Tanya Lewis edited by Claire Cameron

RSV test with baby — RSV test.

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U.S. health officials are reportedly questioning the safety of several approved therapies to treat respiratory syncytial virus (RSV) in babies.

The treatments—specifically, Sanofi and AstraZeneca’s drug Beyfortus and Merck’s drug Enflonsia—are shots that are given to infants in the first months of life to protect against complications from RSV, which is the number one cause of hospitalization in babies in the U.S.

RSV typically hits in winter and can cause severe disease and even death in young babies and older adults. The Centers for Disease Control and Prevention recommends that pregnant people get an RSV vaccine between 32 and 36 weeks of pregnancy during the period from September through January.

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The scrutiny marks the latest move by federal health agencies to question established vaccines and medications under Secretary of Health and Human Services Robert F. Kennedy, Jr., a noted vaccine skeptic. It comes days after a panel of influential vaccine advisors, all of whom were handpicked by Kennedy, voted to rescind the recommendation for a universal birth dose of the hepatitis B vaccine, despite what experts decried as a lack of evidence.

According to Reuters, FDA officials started investigating the RSV therapies over the summer. Vaccine skeptics have claimed, without evidence, that the shots could increase the risk of seizures in some infants.

In 2023 the FDA approved Beyfortus, a type of antibody drug, for babies born during or entering their first RSV season and in children up to two years old who are vulnerable to severe RSV. The agency approved Enflonsia, a similar drug, in June 2025. As with all drugs approved by the FDA, these medications were extensively tested in clinical trials for safety and efficacy before they were given the green light.

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