RFK Jr.’s Vaccine Panel Votes Against Flu Shot Preservative: All About The Controversial Thimerosal Ingredient

A federal vaccine advisory panel, newly reconstituted by U.S. Health Secretary Robert F. Kennedy Jr., has voted against thimerosal, a preservative long used in multi-dose flu vaccines, for use in all age groups. The recommendation, made by a unanimous vote, has caused shock waves in the medical and scientific communities, generating debate on vaccine safety, public confidence, and potential future availability of flu vaccines. The move revisits a debate many experts considered settled and could reshape how influenza vaccines are produced and distributed worldwide.The newly restructured vaccine panel led by U.S. Health Secretary Robert F. Kennedy Jr. voted to advise against the use of thimerosal in flu shots given annually to millions of Americans. The move, taken by the Advisory Committee for Immunization Practices (ACIP), has raised alarm among scientists and public health professionals concerned the ruling could erode confidence in vaccinations and create disruptions in vaccine supplies, particularly during flu season.In a 5-1 vote, with one abstention, ACIP members voted to limit thimerosal in all age groups for seasonal flu vaccines. The revamped panel, reorganized by Kennedy after she had all 17 of the agency's previous members dismissed over charges of conflict of interest, now includes appointees sympathetic to Kennedy's long-time vaccine skepticism."The threat from influenza is so much larger than the non-existent — to our knowledge, at least — threat from thimerosal," said Dr. Cody Meissner, professor of pediatrics at Dartmouth's Geisel School of Medicine and the lone dissenter. "I would be sorry if an individual did not get the influenza vaccine because the only product available contains thimerosal."The Advisory Committee on Immunization Practices (ACIP), which advises the Centers for Disease Control and Prevention (CDC) on vaccine policy, is now in the middle of a storm. In June, Kennedy replaced all 17 of the former members, citing conflicts of interest, and appointed eight new members, many of whom are like-minded skeptics of vaccine safety. Five voted for, one voted against, and one abstained to limit thimerosal in flu vaccines.What is Thimerosal?Thimerosal is an ethylmercury-containing preservative that was first used in the 1930s to stop bacterial contamination of multi-dose vaccine vials. The compound in thimerosal, ethylmercury, is different from methylmercury—the form present in seafood—which is stored in the body and carries known health dangers. Ethylmercury, however, is metabolized and eliminated much faster.The dose of ethylmercury from a standard dose of flu vaccine (25 micrograms) is about half that in a 3-ounce serving of canned tuna (40 micrograms) Thimerosal has been eliminated from almost all routine pediatric and most adult vaccines in the U.S. since the early 2000s as a precaution, even though there was no evidence to implicate it in harm. Now it still appears in only around 5% of multi-dose vials of flu vaccine.Why Is Thimerosal Controversial?Thimerosal became controversial in the late 1990s because it contains mercury and was theorized to cause autism and other neurodevelopmental disorders. Despite repeated, large-scale studies conducted in many countries, numerous studies have determined that there is no connection between thimerosal and neurological injury. The Centers for Disease Control and Prevention, the World Health Organization, and many scientific organizations have all determined that thimerosal, when administered in vaccines, is safe.The preservative has never been part of the MMR vaccine, as is often incorrectly stated. Now, nearly 96% of all flu shots in the United States are thimerosal-free, with only a few kept to serve multi-dose vials for cost-effectiveness and logistical purposes.Despite this, thimerosal was a rallying cry for anti-vaccine activists, including Kennedy himself. Thimerosal-autism theories have been repeatedly discredited, and the preservative was voluntarily phased out from most childhood vaccines in the U.S. by 2001. Significantly, the rates of autism continued to increase even after the removal of thimerosal, further eroding the supposed connection.Several large-scale international studies have identified no link between thimerosal and autism or other neurologic problems. A standard flu shot with thimerosal contains approximately 25 micrograms of ethylmercury — half as much mercury as in a 3-ounce tuna can. Ethylmercury is excreted from the body in approximately a week, with no potential for bioaccumulation.In addition, studies indicate that autism rates have continued to climb even since thimerosal was phased out of children's vaccines in the early 2000s, further refuting the theory that it is responsible for developmental disorders. Implications for Flu Season and Global Vaccine SupplyWhereas the panel again emphasized that all Americans above six months of age should be vaccinated against flu, the vote will potentially restrict access in some settings. Several clinics, particularly in low-income or rural areas, depend on multi-dose thimerosal-containing vials because they are less expensive and easy to store.Experts are concerned that the suggestion might trigger unnecessary shortages or access blockages for underprivileged groups. It also has the potential to impact international vaccine policies, especially in low- and middle-income nations where thimerosal-containing vaccines are still important for logistical and economic reasons.Today, 96% of flu vaccines given in the U.S. are thimerosal-free, with even greater percentages in federal programs such as Vaccines for Children. The majority of children already receive thimerosal-free single-dose vaccines. Nevertheless, the few remaining multi-dose vials are important to maintaining overall vaccine coverage, especially during peak demand or when supplies are low.Although the U.S. has for the most part abandoned thimerosal, it is still used in most global health programs. The World Health Organization has consistently underscored that thimerosal is safe, especially considering its important role in vaccine integrity in poor-world settings.Any change in U.S. policy would have a multiplier effect globally, possibly promoting hesitancy and making supply chains more complex.ACIP's vote is not law, but it is a strong force behind CDC recommendations and insurance payments. It is not clear if the CDC will ultimately endorse the panel's new recommendation. An official announcement from the agency should come before the beginning of next season's flu season.The resurgence of the thimerosal controversy is an outgrowth of deeper stresses in America's public health system. It is a fundamental conflict between scientific consensus and ideological disruption. As flu season approaches, experts caution against vigilance, not only against the virus, but against disinformation.

RFK Jr.’s Vaccine Panel Votes Against Flu Shot Preservative: All About The Controversial Thimerosal Ingredient

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RFK Jr.’s Vaccine Panel Votes Against Flu Shot Preservative: All About The Controversial Thimerosal Ingredient