Flu Vaccine Recommendations: ACIP Updates
- The Advisory Committee on Immunization Practices (ACIP) has recommended thimerosal-free flu vaccines for all adults, children, and pregnant women.The committee also discussed new methods for preventing RSV in...
- The ACIP voted 5-1, with one abstention, to recommend single-dose, thimerosal-free seasonal influenza vaccines for all adults, children under 18, and pregnant women in the U.S.
- Prior to this, the committee reaffirmed its recommendation that everyone 6 months and older without contraindications should receive annual flu shots.
ACIP Recommends Thimerosal-Free Flu shots, New RSV Prevention
Updated June 27, 2025

The Advisory Committee on Immunization Practices (ACIP) has recommended thimerosal-free flu vaccines for all adults, children, and pregnant women.The committee also discussed new methods for preventing RSV in infants.
The ACIP voted 5-1, with one abstention, to recommend single-dose, thimerosal-free seasonal influenza vaccines for all adults, children under 18, and pregnant women in the U.S.
Prior to this, the committee reaffirmed its recommendation that everyone 6 months and older without contraindications should receive annual flu shots. That vote was 6-0 with one abstention.
Thimerosal, a mercury-containing preservative, has been phased out of most childhood vaccines since 2001 due to concerns about neurodevelopmental disorders, despite numerous studies showing no link.While most flu shots are already thimerosal-free, the ACIP’s vote formalizes this preference.
Dr. H. Cody Meissner of Dartmouth Geisel School of medicine, the lone dissenter, voiced concern that the recommendation could limit vaccine access for vulnerable populations. He argued the risk from influenza far outweighs any perceived risk from thimerosal.
The ACIP meeting, led by Dr. Martin Kulldorff, also covered RSV and COVID-19.
For RSV, the committee reviewed data on maternal and pediatric vaccines, including Pfizer’s Abrysvo and Sanofi/AstraZeneca’s Beyfortus. they also discussed Merck’s newly FDA-approved clesrovimab (Enflonsia) for infants. The ACIP voted 6-0, with one abstention, to recommend clesrovimab for infants under 8 months entering their first RSV season who are not protected by maternal vaccination.
Richard M. Haupt of merck Research Laboratories hailed the recommendation as a step toward reducing the burden of RSV on infants and healthcare systems.
Discussions on COVID-19 included updated epidemiological data. While Kulldorff emphasized the importance of evidence-based recommendations, data presented indicated COVID-19 remains a serious threat, and vaccines are effective in preventing hospitalizations.Data also showed that COVID-19 can cause severe disease in young children and pregnant women, but vaccines can provide robust protection.
What’s next
The ACIP’s recommendations will now be reviewed by the CDC for final approval and implementation, perhaps impacting vaccine availability and guidelines for the upcoming respiratory season.
