Under new advisement, the Trump administration’s vaccine experts are revisiting a longstanding debate over flu vaccines that contain the controversial preservative thimerosal. Although past investigations revealed no health risks associated with the compound, panel members recommended that this autumn, individuals should only accept thimerosal-free flu vaccines. Government statistics already indicate that a limited portion of last year’s flu shots included thimerosal, making this recommendation readily achievable.
“This is really a nonissue,” commented Dr. Sean O’Leary from the American Academy of Pediatrics, expressing concern that this renewed focus might foster unnecessary distrust towards safe vaccines.
Thimerosal, in use since the 1930s, serves as a preservative in a variety of vaccines and some other medical products. Primarily, it was used in multi-dose vials to safeguard against bacterial contamination during the withdrawal of doses. Despite its long history, thimerosal became a subject of contention in the late 1990s due to its mercury content.
However, it’s crucial to note that thimerosal contains ethylmercury, as opposed to the more harmful methylmercury found in certain seafood. Ethylmercury is processed and excreted by the body, and no significant harmful effects have been observed at the levels used in vaccines. Moreover, several childhood vaccines like those for chickenpox or measles, mumps, and rubella never utilized thimerosal.
In an abundance of caution, the preservative was removed from childhood vaccines in the U.S. starting in 2001. Nowadays, all vaccines commonly recommended for children ages six and under come free of thimerosal. Only a small portion of flu vaccines in multi-dose vials, intended for adults, contain the preservative. Children primarily receive singe-dose flu shots, which do not contain thimerosal.
Recent data from the Centers for Disease Control and Prevention (CDC) show that 96% of flu vaccines distributed in the latest fall and winter seasons did not contain thimerosal, and this percentage is even higher for federal vaccination programs.
Renewed debate has arisen partly because U.S. Health Secretary Robert F. Kennedy Jr. has long suggested a connection between thimerosal and autism. In a late meeting, his vaccine advisory members considered a presentation by Lyn Redwood, a former president of an anti-vaccine organization. Redwood, now serving as an “expert” in the administration, advocated for the removal of thimerosal from remaining flu vaccines, citing particular concerns for pregnant women.
Nevertheless, a CDC analysis, prepared for the advisory meeting but not publicly presented, reaffirmed that thimerosal is not linked to autism or any neurodevelopmental issues. Moreover, observers emphasize that autism rates continued to grow in the U.S. even after thimerosal was eliminated from children’s vaccines.
While thimerosal’s use persists in vaccines in certain countries, the ongoing discussion underscores the need for informed decision-making based on comprehensive scientific investigation.