WASHINGTON, D.C.: U.S. Health Secretary Robert F. Kennedy Jr. is facing intensifying pressure to resign after more than 20 leading medical organizations accused him of undermining public health and reversing decades of progress.

In a joint statement, the groups said Kennedy's actions, including reshaping vaccine policy and firing the Centers for Disease Control and Prevention's director last week, are putting Americans at risk.

"Our country needs leadership that will promote open, honest dialogue, not disregard decades of lifesaving science, spread misinformation, reverse medical progress, and decimate programs that keep us safe," the statement said.

The signatories include the Infectious Diseases Society of America, the American Academy of Allergy, Asthma & Immunology, the American Public Health Association, and the American Association of Immunologists.

Former CDC directors under both Republican and Democratic administrations have also warned that Kennedy's policies could cost lives. In May, he withdrew federal recommendations for COVID-19 vaccines for pregnant women and healthy children. The following month, he dismissed the CDC's vaccine advisory panel and replaced it with his own appointees, including known vaccine skeptics.

Kennedy defended his actions in a social media post, saying his mission was "to restore the CDC's focus on infectious disease" and "rebuild trust through transparency and competence."

The fallout deepened last week when CDC Director Susan Monarez was removed less than a month into her tenure. Several senior officials resigned in protest. More than 1,000 current and former Health and Human Services employees have since signed an open letter urging Kennedy to step down or be removed.