The US government will withhold funding to Gavi, the global vaccine alliance, until all vaccines containing thimerosal, a mercury preservative, are removed.[1] The move threatens $300 million in the fiscal year 2026 funding bill passed by the House of Representatives, which is still pending Senate approval.[2] A Department of Health and Human Services official told Reuters that the US would withhold future new funding.[1] The United States is one of Gavi's original donors and accounts for approximately 13% of its funding.[4] Gavi helps vaccinate children in developing countries, and it is estimated that the loss of US funding would mean 75 million fewer children vaccinated over the next five years, 1.2 million of whom would lose their lives.[1] Only thimerosal-free single-dose flu vaccines are recommended in the US.[1]