A Senate Health, Education, Labor, and Pensions Committee hearing on Wednesday spotlighted a clash over vaccines for infants as Sen. Rand Paul, R-Ky., pressed top Democrat Sen. Bernie Sanders and former CDC director Susan Monarez about the science behind vaccinating six-month-old children. The session was convened to discuss Health and Human Services Secretary Robert F. Kennedy Jr.'s decision to oust Monarez last month.
Paul argued there is little evidence of a clear benefit from vaccinating infants against certain diseases and pressed for the scientific basis behind including vaccines on the infant schedule. He asked: “When we're discussing the science here, we have to discuss what is the science in favor of giving the vaccine to a 6-month-old, and what are the benefits from that? And there is no benefit of hospitalization or death. And then what would the risks of that vaccine be? We have large population studies of the risks of the vaccine in younger people.” Sanders interjected as Paul pressed Monarez for a response, noting the former CDC chief’s firing and challenging the administration to defend the policy, while Monarez did not immediately answer.
Paul then turned to an example that has drawn heightened scrutiny: the Hepatitis-B vaccine for newborns. He pressed, “What is the medical, scientific reason and proof for giving a newborn a Hepatitis-B vaccine if the mom is Hep-B negative?” Sanders interrupted again as Paul spoke over Monarez, who did not directly answer the question. Paul asserted that the burden should be on the administration to prove that vaccines recommended for infants are helpful, saying, “The burden should be on you.”
Monarez, who testified amid the dispute over her departure, said she was told she was being fired for reasons tied to CDC personnel decisions but did not concede specifics about her replacement. She maintained there is no scientific justification for removing vaccines from the recommended list, though she did not directly address Paul’s Hep-B question during the exchange.
The back-and-forth reflected mounting bipartisan concern about CDC guidance and a broader fight over the role of scientific advice in vaccination policy. Several senators urged an independent review of the agency’s vaccine recommendations and criticized the administration’s handling of personnel changes at the CDC as contributing to public confusion about vaccines.
The hearing underscores ongoing debates that extend beyond the Kennedy‑Monarez dispute, illustrating partisan tensions over how vaccine science is translated into policy and how personnel decisions at the CDC are perceived to influence public health messaging. Kennedy’s decision to replace Monarez last month has become a focal point for critics who allege political interference, while supporters say leadership changes reflect a re-evaluation of the agency’s vaccine guidance. As the committee session concluded, lawmakers signaled they would pursue further oversight and seek additional testimony on the CDC’s vaccine recommendations and related personnel matters.