Sen. Bill Cassidy, a Louisiana Republican and chairman of the Senate Health, Education, Labor and Pensions Committee, used a confirmation hearing Wednesday to publicly challenge the Trump administration’s approach to vaccines, linking its policies to recent measles deaths in Pennsylvania.

Cassidy called the outbreak a “terrible legacy for this administration” and accused federal officials of allowing misinformation and what he described as misguided policies to leave Americans vulnerable to a preventable disease. His remarks came as the committee questioned three of President Donald Trump’s nominees for senior health positions.

Cassidy repeatedly pressed Surgeon General nominee Dr. Nicole Saphier on vaccine safety, including whether childhood vaccines cause autism. Saphier ultimately told senators that she does not believe childhood vaccines cause autism and described the measles, mumps and rubella vaccine as an important tool for combating measles.

Cassidy also criticized Trump’s recent effort to alter the childhood vaccine schedule. The administration has defended its changes as an effort to base federal vaccine policy on scientific review and provide parents with more information. The White House and Health and Human Services have rejected the claim that the administration is discouraging measles vaccination, noting that HHS Secretary Robert F. Kennedy Jr. has continued to identify the MMR vaccine as the most effective way to prevent measles.

Pennsylvania has reported 731 measles cases across 38 counties in 2026, along with four measles-associated deaths. The state Department of Health says all four individuals were unvaccinated, although the two infants among the fatalities were too young to receive the vaccine.

Cassidy also questioned why the Centers for Disease Control and Prevention had not yet included Pennsylvania’s deaths in its national measles mortality tally. CDC officials have said they are working to establish a consistent definition for measles-related deaths. Cassidy argued that Americans should have access to clear information about deaths associated with the outbreak.

The hearing highlighted an increasingly public disagreement between Cassidy and Trump administration officials over vaccine policy. While Cassidy has argued that recent federal changes could undermine confidence in childhood immunizations, administration officials maintain that their policies are intended to strengthen scientific review and preserve access to recommended vaccines.