In consultation with the Pennsylvania Department of Health, the county Health Department is recommending that students, teachers, and support staff who have had one dose of a mumps-containing vaccine and are considered to be immune receive a second dose, according to the Berrios letter. Those who are not immune and have never received a mumps-containing vaccine should stay home until they are vaccinated or through June 12, the school district said. The MMR (measles, mumps, and rubella) vaccine is recommended for children between 12 and 15 months of age, with a second dose between 4 and 6 years of age.