From the Guidelines
The MMR vaccination should not be given earlier than 12 months of age in routine circumstances, but it can be administered as early as 6 months of age in special situations, such as during measles outbreaks or before international travel to high-risk areas, as stated in the recommendations of the Advisory Committee on Immunization Practices (ACIP) 1.
Routine Vaccination Schedule
The standard recommendation is to administer the first dose of MMR vaccine at 12-15 months of age, followed by a second dose at 4-6 years of age.
- The MMR vaccine is typically given in combination with the varicella vaccine as MMRV vaccine, but MMR vaccine and varicella vaccine can be administered separately if preferred or if there are concerns about the risk of adverse events 1.
- The immune response to vaccination before 12 months is often suboptimal due to the presence of maternal antibodies, which typically wane between 6-12 months after birth.
Special Circumstances
In special situations, such as during measles outbreaks or before international travel to high-risk areas, an early dose of MMR vaccine may be given to infants 6-11 months old, but this dose does not count toward the routine two-dose series.
- Children who receive an early dose of MMR vaccine still need to receive the standard doses at the recommended ages to ensure full protection 1.
- The ACIP recommendations for use of MMRV vaccine have been summarized, and the routinely recommended ages for measles, mumps, rubella, and varicella vaccination continue to be 12–15 months for the first dose and 4–6 years for the second dose 1.
From the Research
MMR Vaccination Administration
- The MMR vaccine is typically administered to children at 12 through 15 months of age, with a second dose given at 4 through 6 years of age 2.
- However, in certain situations, such as outbreaks or travel to areas with high disease prevalence, the vaccine may be given earlier, but there is no specific recommendation for administration earlier than 6 months of age 2.
- For infants aged birth to 6 months exposed to measles, immune globulin administered intramuscularly (IGIM) is recommended, rather than the MMR vaccine 2.
Special Populations
- For persons with human immunodeficiency virus (HIV) infection, the MMR vaccine is recommended for all persons aged ≥12 months who do not have evidence of current severe immunosuppression 2.
- The vaccine may be given to HIV-infected persons at 12 through 15 months and 4 through 6 years of age, with revaccination recommended for those who were vaccinated before establishment of effective antiretroviral therapy (ART) 2.
Vaccine Effectiveness and Safety
- The MMR vaccine has been shown to be effective in preventing measles, mumps, and rubella, with one dose being at least 95% effective in preventing clinical measles and 92% effective in preventing secondary cases among household contacts 3.
- The vaccine has also been shown to be safe, with no increased risk of autism, asthma, leukemia, hay fever, type 1 diabetes, gait disturbance, Crohn's disease, demyelinating diseases, bacterial or viral infections 3.
- However, there is a small increased risk of aseptic meningitis, febrile seizures, and thrombocytopenic purpura associated with the vaccine 3.