U.S. health manufacturers and experts raised alarms after reporting that the administration—led by Health Secretary Robert F. Kennedy Jr.—is weighing major vaccine policy changes, including discouraging adjuvant ingredients and breaking up combination childhood shots. Companies warned such moves could force years‑long redevelopment efforts, threaten supply of established childhood vaccines, and reduce protection against diseases like measles and polio. The proposals follow broader changes at federal agencies, including wholesale personnel shifts at ACIP, and have prompted private warnings from industry that rapid regulatory shifts could take a decade and cost over $1 billion to retool vaccines. Public‑health and manufacturer sources say reforms could cause short‑term shortages and long‑term changes to vaccine design, manufacturing and schedules. Sources: STAT reporting and public statements from vaccine makers and officials.