President Trump signed an executive order significantly overhauling federal childhood vaccine recommendations, cutting the number of recommended jabs from 18 to 11 and requiring several to be split into separate doses spread across more medical appointments. The move is not grounded in new scientific evidence but reflects long-debunked anti-vaccine claims, including that vaccines cause autism and that combining shots "overwhelms" children's immune systems, and comes as US vaccination rates are already falling and measles cases are at their highest since 1991.

At a White House signing event, Trump made a series of false claims, including that the MMR combination vaccine is "quite lethal" and that giving children multiple vaccines has caused an "epidemic" of autism, despite dozens of large studies finding no such link. He also praised Health Secretary Robert F. Kennedy Jr., a prominent vaccine sceptic who has reportedly faced pressure from Trump to tie vaccines to autism. The order calls for splitting the MMR vaccine into three separate shots, even though no such individual vaccines currently exist in the US and developing them would take years of costly trials; the existing combined MMR vaccine has been used safely for decades with 97 percent efficacy. Only 10 US states currently meet the 95 percent vaccination threshold needed to prevent outbreaks, and the country has recorded 2,465 measles cases this year, putting its measles elimination status at risk.