U.S. Secretary of Health and Human Services Robert F. Kennedy Jr. confronted rigorous questioning and criticism during a Senate Finance Committee hearing focused on vaccine policy upheaval and leadership changes at the Centers for Disease Control and Prevention (CDC). Senators from both parties expressed concerns over policy reversals, staffing instability, and the sidelining of long-standing scientific advisory panels. The firing of CDC Director Susan Monarez and subsequent departures of senior agency scientists intensified calls for Kennedy’s resignation. Health advocacy groups condemned actions perceived as undermining public health progress on immunizations. The contentious hearing underscored sharp political divides and raised alarms about current vaccine oversight and public health strategy coherence in the United States.