MMR Vaccination for Individuals Without Immunity
Two doses of MMR vaccine should be administered to individuals without immunity to measles, mumps, and rubella, with doses separated by at least 28 days. 1
General Recommendations for MMR Vaccination
Children
- Children should receive their first dose of MMR vaccine at 12-15 months of age 1
- The second dose is recommended at 4-6 years of age (before kindergarten or first grade) 1
- For children who have not received the vaccine on schedule, two doses should be administered at least 28 days apart 1
- If a child is behind schedule, there is no need to restart the vaccine series regardless of time elapsed between doses 1
Adults
- Adults born in 1957 or later without evidence of immunity should receive at least one dose of MMR vaccine 1
- A second dose of MMR vaccine is recommended for adults at higher risk of exposure and transmission, including:
Special Populations and Situations
Infants and Young Children
- Before international travel, infants aged 6-11 months should receive a single dose of MMR 1
- During measles outbreaks, infants aged 6-11 months should also receive a single dose 1
- In both cases, these children will still need two additional doses starting at 12-15 months to complete the series 1
Measles Post-exposure Prophylaxis
- For unvaccinated persons, one dose of MMR should be administered within 72 hours of exposure to a person with infectious measles 1
- The second dose should be completed ≥28 days later to complete the series 1
Mumps Outbreak Response
- During mumps outbreaks, a third dose of MMR is recommended for persons identified by public health authorities as being part of a group at increased risk 1
Evidence of Immunity
Acceptable evidence of immunity to measles, mumps, and rubella includes:
- Documentation of age-appropriate vaccination 2, 3
- Laboratory evidence of immunity 2, 3
- Laboratory confirmation of disease 2, 3
- Birth before 1957 (except for healthcare personnel) 2
Vaccine Interchangeability and Administration
- MMR vaccines from different manufacturers (such as PRIORIX and M-M-R II) are considered fully interchangeable 1
- Additional live virus vaccines not administered on the same day should be separated by ≥4 weeks 1
- The MMR vaccine has demonstrated robust immune responses with seroconversion rates of >98% for all three components after two doses 4, 5
Common Pitfalls and Considerations
- Documentation of provider-diagnosed disease is no longer considered acceptable evidence of immunity for measles and mumps 2, 3
- Women of childbearing age should be considered susceptible to rubella unless they have received at least one dose of MMR or have serologic evidence of immunity 1, 2
- MMR vaccine should not be administered to pregnant women or those planning to become pregnant within 4 weeks 2
- Healthcare personnel born before 1957 should not be assumed to be immune; consideration should be given to testing for immunity or vaccinating 2
The two-dose MMR vaccination strategy has been highly effective in providing long-term immunity, with studies showing sustained antibody levels for at least 3 years following vaccination 6, 7.