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CDC advisers vote to drop thimerosal from flu shots

June 27, 2025

In a controversial decision, CDC’s Advisory Committee on Immunization Practices (ACIP) voted on June 26 to recommend against the use of thimerosal-containing influenza vaccines for all age groups beginning in the 2025–26 flu season. The vote, which passed 5 to 1 across all categories, favors single-dose, preservative-free formulations, despite decades of research affirming thimerosal’s safety.

The decision marks a significant shift in U.S. vaccine policy, especially given that thimerosal was removed from most vaccines over two decades ago as a precaution, not due to safety concerns. Today, all routine childhood vaccines are thimerosal-free, with the preservative remaining only in a small fraction of some multi-dose flu shots.

CDC emphasized that the recommendation was not based on new safety data but on a desire to “reestablish confidence in the scientific examination process.”

The vote comes amid broader changes at CDC under Health Secretary Robert F. Kennedy Jr., whose recent appointments have drawn scrutiny for their alignment with vaccine-skeptical views. With no CDC director currently in place, Health Secretary Kennedy is responsible for approving ACIP’s recommendations.

Sources:

(2025, June 26). CDC. CDC’s Advisory Committee on Immunization Concludes Meeting with Joint Statement. [News release]. https://www.cdc.gov/media/releases/2025/2025-cdcs-advisory-committee-on-immunization-concludes-meeting-with-joint-statement.html

Goodman, B, et al. (2025, June 26). CNN. New CDC vaccine advisers endorse thimerosal-free flu vaccines, despite no evidence of harm from the preservative. https://www.cnn.com/2025/06/26/health/cdc-acip-vaccines-rsv-thimerosal

Stone, W, et al. (2025, June 26). NPR. RFK Jr.'s vaccine advisers raise disproven fears about the preservative thimerosal. https://www.npr.org/sections/shots-health-news/2025/06/26/nx-s1-5438485/cdc-acip-rfk-thimerosal-vaccines