The Brief President Donald Trump signed an executive order calling for childhood vaccines to be spread across more medical visits. The order recommends separating the MMR vaccine into three individual shots given at different visits. President Donald Trump signed an executive order on Monday that called for spacing out childhood vaccines. Dig deeper:The order separates the measles, mumps and rubella (MMR) vaccine into three different shots to be administered at three separate visits. Trump also said that one-year-olds should have their shots separated into five different visits.