From the Guidelines
The MMR vaccine is typically administered to children in two doses, with the first dose recommended at 12-15 months of age and the second dose given at 4-6 years of age. This schedule ensures optimal immune response and protection against measles, mumps, and rubella, as recommended by the Advisory Committee on Immunization Practices (ACIP) 1. The timing of the first dose is carefully selected to balance between waiting for maternal antibodies to decrease (which could interfere with vaccine effectiveness) and providing protection before likely exposure to these diseases.
- The second dose is not a booster but serves to produce immunity in those who did not respond to the first dose.
- For children who miss these recommended ages, catch-up vaccination can be provided at any visit as long as the minimum interval between doses is maintained.
- In outbreak situations or before international travel, infants as young as 6 months may receive an early dose, but this would not count toward the routine two-dose series. The most recent guidelines from 2022 support this schedule, emphasizing the importance of completing the two-dose series for optimal protection 1. While earlier studies and guidelines also support this schedule 1, the 2022 recommendation from the ACIP is the most current and authoritative guidance on MMR vaccine administration.
From the Research
MMR Vaccine Administration Age
The Measles, Mumps, and Rubella (MMR) vaccine is typically administered at the following ages:
- 12-15 months: The first dose of MMR vaccine is usually given to infants at this age, as stated in the study 2.
- 4-6 years: A second dose of MMR vaccine is recommended at this age, according to the study 3.
- 10-12 years: Some studies, such as 4, have compared the adverse clinical events after immunization at this age group with those at 4-5 years of age.
Additional Considerations
Some studies have also explored the immunogenicity and safety of MMR vaccine administration at different ages, including:
- 8 months: A study 5 found that administering the first dose of MMR vaccine at 8 months of age was well-tolerated and immunogenic.
- 12 months: Another study 6 compared the immunogenicity and efficacy of one dose of MMR vaccine at 12 months of age with monovalent measles vaccination at 9 months followed by MMR revaccination at 15 months of age.
Key Findings
The studies suggest that:
- The MMR vaccine is highly immunogenic, with seroconversion rates of 95 to 100% being achieved for each of the three component vaccines 2.
- The vaccine is well-tolerated, with minor adverse effects occurring approximately 1 week after immunization 2.
- The risk of clinical events after MMR2 immunizations may be greater in the 10- to 12-year age group compared to the 4- to 6-year age group 4.