Read our Privacy noticePresident Donald Trump signed an executive order that significantly altered the federal guidance for childhood vaccines and call for states to reconsider their requirements for school, upending decades of public health practice. Citing no evidence, he alleged that the MMR vaccine — long a boogeyman of anti-vaccine activists thanks to a long-discredited study by a disgraced British ex-physician–is dangerous. open image in gallery President Donald Trump announced sweeping changes to the nation’s childhood vaccine recommendations by signing a new executive order ( AFP/Getty )“So the MMR, we want to have separate, separate visits, separate times. The vaccine being broken into three separate single doses, and vaccines being administered in separate visits,” he said. This comes despite the fact that multiple studies have debunked the supposed link between childhood vaccinations and children developing autism spectrum disorder.