With US Health and Human Services Secretary Robert F. Kennedy, Jr. already shaking up federal vaccine policy, some states are stepping in to preserve access to lifesaving shots in anticipation of further changes.

The federal government has historically had a major influence on vaccine policy through the Advisory Committee on Immunization Practices (ACIP), formed in 1964 to develop science-based recommendations on how vaccines should be used. The recommendations are almost always adopted by the Centers for Disease Control and Prevention, and in many states, these recommendations are tied to insurance coverage. If ACIP no longer recommends certain vaccines, individuals could be forced to pay out-of-pocket for livesaving vaccines that have long been provided at no cost.

A longtime anti-vaccine activist, Kennedy announced in May that the CDC will no longer recommend Covid-19 shots for healthy children and pregnant women. In June, he fired all 17 sitting members of ACIP and installed eight new members, several of whom are critical of vaccines. “A clean sweep is necessary to reestablish public confidence in vaccine science,” Kennedy said in an agency statement.

During the new committee’s first meeting at the end of June, members voted to recommend banning the preservative thimerosal from flu vaccines. The move was largely symbolic since thimerosal has not been in any routine childhood vaccines in the US since 2001. It was removed due to growing public backlash, despite the fact that it has been shown to be safe. Now, thimerosal is only used in some multi-dose vials of the influenza vaccine, which represent a small percentage of all flu vaccines given in the US. HHS adopted AC...