An executive order signed by Donald Trump with little fanfare on Friday could have a huge impact on the health of US children, as it instructs the Centers for Disease Control and Prevention (CDC) to cut the number of recommended childhood vaccines almost in half.The vague language of the order, which refers to “a scientific assessment that compared United States childhood immunization recommendations with those of peer nations” published in January by anti-vaccine activist Robert F Kennedy’s health and human services department, does not explicitly state that the new recommendation removes vaccines against seven diseases from the schedule.The assessment, co-authored by the subsequently fired vaccine skeptic Dr Tracy Beth Høeg, concluded that the CDC director should update the childhood immunization schedule “to keep vaccines for 10 diseases – measles, mumps, rubella, polio, pertussis, tetanus, diphtheria, Haemophilus influenzae type B (Hib), pneumococcal disease, and human papillomavirus (HPV) – for which peer, developed nations share international consensus, as well as varicella (chickenpox) … in the category of vaccines recommended for all children”.Implementing that recommendation would mean removing vaccines for these diseases from the recommended schedule: