For the first time, all influenza vaccines distributed in the U.S. will be free of thimerosal, following a formal policy shift by the Department of Health and Human Services.
On July 23, 2025, U.S. Health and Human Services (HHS) Secretary Robert F. Kennedy, Jr. signed the Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunization Practices (ACIP) recommendation to eliminate thimerosal from all influenza vaccines distributed in the U.S. The decision followed a 5-1-1 vote at the ACIP’s June 25 to 26 meeting, during which the committee recommended that all pediatric, adult, and prenatal influenza immunizations be administered exclusively in single-dose, mercury-free formulations.
In 1999, the U.S. Public Health Service, the American Academy of Pediatrics, and vaccine manufacturers reached a joint agreement to begin removing mercury from childhood vaccines due to concerns about potential risk. This latest directive completes that transition by removing thimerosal from all remaining influenza vaccines.
According to the HHS, manufacturers have confirmed adequate production capacity for single-dose thimerosal-free vaccines, including those supplied through the Vaccines for Children program and adult immunization channels. The policy is not expected to affect vaccine availability or distribution logistics.
The ACIP, comprising experts in infectious diseases, epidemiology, and public health, provides recommendations to the CDC regarding immunization practices based on available evidence on safety, efficacy, and public health impact. This recommendation aligns U.S. policy with that of several European nations that previously removed mercury-containing additives from vaccines.
The decision is positioned by HHS as a measure to reduce unnecessary mercury exposure, particularly among vulnerable populations, while maintaining confidence in vaccine safety. Secretary Kennedy, who has approved all recommendations from the ACIP’s April session, stated that the remaining recommendations from the committee’s June meeting are still under review.
No supply disruptions are anticipated.