The MMR vaccine schedule is the most controversial changeThe executive order calls for the combined MMR vaccine schedule to be replaced, once possible, with three separate single-disease shots for measles, mumps and rubella. The order therefore does not mean that American pediatricians can begin giving children three separate MMR injections immediately. But the scientific evidence does not establish that MMR vaccination causes autism. Merck, which manufactures the combined MMR vaccine, said there is no published scientific evidence demonstrating a benefit from splitting the combination vaccine. The administration’s stated objective is to create what it calls “Gold Standard Childhood Vaccine Recommendations.”