RFK, HHS OKs Removal of Thimerosal From Influenza Vaccines

Image credit: CDC, Pexels

Health and Human Services (HHS) Secretary Robert F. Kennedy has adopted the recommendation of the CDC’s ACIP to remove thimerosal from influenza vaccines.¹

This adoption follows a 5-1-1 vote at the ACIP’s meeting in June 25-26 meeting, where committee members voted that all children 18 years and younger, pregnant women, and adults receive only single-dose influenza vaccines free of thimerosal.¹

It is important to note that thimerosal is an ethylmercury-containing preservative in some multi-dose preparations of flu vaccine. It’s use has been to prevent bacterial growth in the vaccines. Although there have been concerns around potential mercury effects, thimerosal has not been found to cause health issues in children or affect the unborn children of pregnant women. Thimerosal contained in vaccines is not harmful, according to the Children’s Hospital of Philadelphia.²

Additionally, there have been studies looking at this and there has been no scientific evidence linking thimerosal to autism.³

“Thimerosal use in medical products has a record of being very safe. Data from many studies show no evidence of harm caused by the low doses of thimerosal in vaccines,” CDC writes on its site.³

“Other than allergic responses in some individuals, there was no known health risk from thimerosal-preservative at the concentration used in vaccines, but in 1999, the Public Health Service (including the FDA, National Institutes of Health (NIH), CDC, and Health Resources and Services Administration (HRSA)), along with the American Academy of Pediatrics (AAP) and the American Academy of Family Physicians (AAFP) concluded that because of scientific uncertainty at the time, as a precautionary measure, that it was prudent to reduce childhood exposure to mercury from all sources, including vaccines, to the extent feasible,” the FDA writes on its site.⁴

In July of that same year, FDA sent a letter to all manufacturers of US licensed vaccines requesting that thimerosal be removed.⁴

“This step was taken because the elimination or reduction of mercury in vaccines was a feasible means of reducing an infant’s total exposure to mercury in a world where other environmental sources of mercury are challenging to eliminate,” FDA said.⁴

According to the HHS statement this week, vaccine manufacturers have confirmed they have the capacity to replace multi-dose vials containing thimerosal, ensuring the Vaccines for Children (VFC) program and adult vaccine supplies will remain uninterrupted.¹

References
1. HHS Adopts ACIP Recommendation to Remove Thimerosal from All U.S. Influenza Vaccines. HHS. July 23, 2025. Accessed July 24, 2025.
https://www.hhs.gov/press-room/thimerosal-mercury-removed-from-us-flu-vaccines-acip.html
2. Vaccine Ingredients: Thimerosal. CHOP. Reviewed June 1, 2020. Accessed July 24, 2025.
https://www.chop.edu/vaccine-education-center/vaccine-safety/vaccine-ingredients/thimerosal
3. Thimerosal and Vaccines. CDC. December 19, 2024. Accessed July 24, 2025.
https://www.cdc.gov/vaccine-safety/about/thimerosal.html
4. Thimerosal and Vaccines. FDA. January 15, 2025. Accessed July 24, 2025.
https://www.fda.gov/vaccines-blood-biologics/safety-availability-biologics/thimerosal-and-vaccines#action