Cassidy Presses Trump Administration on Vaccines as U.S. Measles Cases Top 4,000

Since Pennsylvania's outbreak passed 1,000 cases and a sixth measles-linked death was confirmed there this week, the fight over how Washington is responding has moved into the Senate. The loudest critic is a Republican.

Sen. Bill Cassidy of Louisiana chairs the Senate Health, Education, Labor and Pensions Committee. He is also a physician. He told CNN's Jake Tapper that the Trump administration is not promoting vaccination vigorously enough.

"I have seen people die from vaccine-preventable diseases. You get vaccinated, you don't die. You're not vaccinated, you do die," Cassidy said.

The numbers behind the criticism

The CDC reported Friday that U.S. measles cases this year have topped 4,000. About 96 percent of them are tied to known outbreaks.

For all of 2025, the agency counted 2,289 infections.

About 95 percent of the people infected this year were unvaccinated or had an unknown vaccination status, according to the CDC.

Pennsylvania has recorded more than 1,100 cases, its largest measles outbreak in decades. Six deaths have been linked to it. Health Secretary Robert F. Kennedy Jr. and Gov. Josh Shapiro, a Democrat, have been feuding over the true death toll.

Cassidy's case

Cassidy framed the issue as one of public health, not just personal choice. "My concern as a physician is that everyone should be vaccinated for measles," he said. "And you may think it only affects me. That's not true because you infect other people."

He added: "If I'm not protected, but you are, then I'm not exposed. I'm all about asking people to be immunized for yourself and for others."

He urged Kennedy and the CDC to do more. He also acknowledged that Kennedy, who has promoted theories linking vaccines to autism and other conditions, has encouraged immunization. His argument is that the effort falls short.

This is not Cassidy's first swing. At an earlier hearing for three HHS nominees, he called the administration's handling of measles outbreaks a "terrible legacy" and cited the Pennsylvania deaths.

The FDA nominee takes questions

The pressure carried into the confirmation hearing for Dr. Heidi Overton, Trump's pick to run the Food and Drug Administration. She has been a White House domestic policy official overseeing health initiatives.

Overton told the committee that the MMR vaccine is safe and effective and called it "not lethal." She described it as "our best tool right now in the public health response to the measles outbreak." CNN reported that this appeared to break with Trump, who has claimed otherwise.

Cassidy asked whether any vaccines on the U.S. market are unsafe. "Every vaccine on the US market right now are safe and effective, according to the FDA," Overton answered.

He then asked what she would do if the president told her to act against the science. She said she would give Trump her best advice and follow the statutory requirements for FDA commissioners on safety and efficacy determinations for individual products.

The executive order

Cassidy and other senators pressed Overton on her role in Trump's executive order on vaccines. The order aims to scale back the number of vaccinations routinely recommended for children. It also prioritizes splitting the MMR shot into individual components given at separate medical visits.

Trump has said some routine immunizations would be split into five separate shots. Vaccine experts told CNN the approach would reduce uptake of the vaccine and worsen the measles numbers, which are at their highest since the disease was declared eliminated in the U.S. decades ago.

The administration's side is thinner on the record. Cassidy himself conceded that Kennedy has urged vaccination. The sources do not include a White House or HHS rebuttal to the argument that splitting the vaccine will hurt uptake.

The FDA's leadership gap

The agency has been without a confirmed leader since Dr. Marty Makary resigned in May under intense pressure. Kyle Diamantas, the deputy commissioner for food, has served as acting commissioner.

A senior administration official told CNN that Diamantas repeatedly turned down the permanent job, even when Trump asked him directly.

The HELP Committee, which Cassidy chairs, will vote on whether to advance Overton's nomination to the full Senate. That vote has not yet been held. Her answers on MMR safety and on following statutory requirements over presidential direction will be part of the record the committee votes on.