WHO warns Trump's childhood vaccine overhaul defies decades of evidence

Trump's executive order

On Monday, August 10, President Donald Trump signed an executive order aimed at fundamentally reshaping the federal government's approach to childhood immunisation. The order reduces the number of recommended vaccinations in early childhood, calls for a rethink of school vaccine mandates, and proposes splitting the trivalent measles, mumps and rubella (MMR) vaccine into three separate administrations. The pediatric vaccine schedule would be divided into three categories. All children would still be recommended to receive vaccines against measles, mumps, rubella, diphtheria, tetanus, pertussis, polio, Haemophilus influenzae type B, pneumococcal disease, HPV and varicella. Only children in high-risk categories would receive monoclonal antibodies against respiratory syncytial virus (RSV) and vaccines against hepatitis A, hepatitis B, meningococcus B, meningococcus Acwy and dengue. For other vaccines, including rotavirus, meningococcal disease, influenza and Covid-19, the decision would be left to parents and the child's physician.

WHO response

WHO Director-General Tedros Adhanom Ghebreyesus warned on August 12 that the changes are "not aligned with decades of evidence." Speaking at a press conference in Geneva and posting on X, Tedros said the science is "unequivocal" and that vaccines, including the MMR vaccine, are safe and do not cause autism.

“Vaccination policy should be guided by rigorous, independent and transparent review of the best available science, not by political influence.”

Tedros warned that delaying vaccines or separating doses unnecessarily does not make vaccination safer and can leave children unprotected. WHO experts noted that the MMR combination vaccine protects many children simply and effectively, and that splitting it into multiple appointments would increase the burden on parents, potentially leaving children without all the necessary doses and raising the risk of illness and death.

“That goes exactly in the wrong direction.”

Kennedy's role and political context

Health Secretary Robert F. Kennedy Jr, who founded an anti-vaccine group and has long promoted a disproven link between the MMR shot and autism, has launched a sweeping review of longstanding vaccines, rewritten the childhood immunisation schedule, and cut funding for new vaccine development. Trump has urged Kennedy to accelerate the review of the vaccine schedule and research into a possible relationship between vaccines and autism. Numerous scientific studies have found no evidence of a causal link between vaccinations and autism. Trump has repeatedly linked his new policy to the rising number of autism diagnoses.

Legal and epidemiological backdrop

US courts earlier in 2026 suspended a vaccination policy shake-up Kennedy had initiated. In January, the Department of Health and Human Services had already sought to reduce the number of recommended vaccinations in the pediatric calendar; medical organisations challenged the changes and a judge ruled in their favour. The executive order comes as the US is experiencing its worst measles outbreak in 35 years, with children across the country preparing to return to school, a situation likely to further spread infections. Trump announced the US withdrawal from the WHO on his first day back in office in 2025, after 77 years of membership.