Recent actions spearheaded by Robert F Kennedy Jr during the Trump administration have significantly hampered the US’s capacity to manage outbreaks and infectious disease threats, reports recently dismissed personnel from the US Centers for Disease Control and Prevention (CDC).

The two former top officials testified at a hearing on Wednesday before the Senate HELP (Health, Education, Labor and Pensions) committee.

Susan Monarez, appointed as the CDC director by Kennedy, was removed from her position in under a month. Debra Houry, the CDC’s chief medical officer, stepped down following her service under six different CDC directors in both Republican and Democratic administrations.

On the morning of August 25, Kennedy insisted that Monarez “agree in advance to endorse every ACIP recommendation, regardless of scientific scrutiny,” she testified. He also instructed her to discharge career officials in charge of vaccine policy without valid reason, as per her statement.

“He stated that if I declined to fulfill both conditions, I should step down. I replied that I couldn’t approve recommendations without examining the scientific data, nor did I have grounds to dismiss scientific experts,” Monarez asserts this is the actual reason behind her dismissal.

The CDC’s vaccine advisory committee, ACIP, which has been replaced with Kennedy’s handpicked advisers, will meet on Thursday and Friday.

“From my observations during my time at the CDC, there is a tangible risk that recommendations could restrict vaccine access for children and others in need without thorough scientific evaluation. In the absence of a permanent CDC director, those recommendations might be implemented,” Monarez added.

“The implications are not merely hypothetical. We have already experienced the most substantial measles outbreak in over 30 years, resulting in the tragic loss of two children’s lives. If vaccine safeguards are weakened, preventable diseases are likely to resurface,” she warned.

Also on 25 August, Monarez said Kennedy told her “the childhood vaccine schedule would be changing starting in September, and I needed to be on board with it”. She said Kennedy had the support of the Trump White House, with Kennedy claiming to her that “he spoke to the President every day about changing the childhood vaccine schedule”.

Debra Houry also testified to seeing political interference.

“I resigned because CDC leaders were reduced to rubber stamps, supporting policies not based in science, and putting American lives at risk. Secretary Kennedy censored CDC science, politicized its processes and stripped leaders of independence,” Houry said.