title: Measles vaccine once or MMR twice?
mesh_terms: D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D007115:Immunization Schedule; D007223:Infant; D008297:Male; D008458:Measles Vaccine / Q000008:administration & dosage*; D009108:Mumps Vaccine / Q000008:administration & dosage*; D012411:Rubella Vaccine / Q000008:administration & dosage*
chemical_list: D008458:Measles Vaccine; D009108:Mumps Vaccine; D012411:Rubella Vaccine