Measles, Mumps, and Rubella (MMR) Vaccine

The measles/mumps/rubella vaccine contains live-attenuated measles and mumps viruses, prepared in chicken embryo cell cultures. It also contains live-attenuated rubella virus prepared in human diploid lung fibroblasts.

The MMR vaccine and varicella vaccine are available as a combined MMRV vaccine (measles virus/mumps virus/rubella virus/varicella virus vaccine).are available as a combined MMRV vaccine (measles virus/mumps virus/rubella virus/varicella virus vaccine).

The MMR vaccine is a routine childhood vaccination (1).

People born before 1957 experienced multiple years of measles epidemics prior to the introduction of the first vaccine in 1963 and are presumed to be immune, and surveys indicate that 95% to 98% of them likely contracted the disease (2). All adults who were born in 1957 or later should be given 1 dose of the vaccine unless they have one of the following (3):

• Documentation of vaccination with 1 or more doses of MMR vaccine

• Laboratory evidence that indicates immunity to all 3 diseases

• A contraindication to the vaccine

A clinical diagnosis of disease by a physician without laboratory confirmation is not considered acceptable evidence of immunity to measles, mumps, or rubella. International travelers (including infants 6 to 12 months old) who do not have presumptive evidence of measles immunity and who have no contraindications to MMR or MMRV vaccine should ideally receive either vaccine at least 2 weeks before travel (4).

A second dose of MMR vaccine (or, if they have not been vaccinated, 2 doses administered ≥ 28 days apart) is recommended for adults who are likely to be exposed (5):

• Students in colleges or other post–high school educational institutions

• Health care workers born in 1957 or later with no evidence of immunity

• People anticipating exposure to outbreak settings or international travelers

• Patients with HIV infection, CD4 ≥ 15% and CD4 cell count ≥ 200/mcL for ≥ 6 months, and no evidence of immunity to measles, mumps, or rubella

People born before 1957 and those who work within health care facilities (whether or not they have patient care duties) should be considered for vaccination if they have no evidence of immunity (2). Two doses of MMR vaccine are administered (1 dose if only rubella coverage is needed).

People who were vaccinated with inactivated measles vaccine or measles vaccine of unknown type during 1963 to 1967 should be revaccinated with 2 doses of MMR vaccine.

People who were vaccinated before 1979 with inactivated mumps vaccine or mumps vaccine of unknown type and who are at high risk of mumps exposure should be offered revaccination with 2 doses of MMR vaccine.

If people aged ≥ 12 months were previously given ≤ 2 doses of mumps-containing vaccine and are identified by public health authorities to be at increased risk of mumps during a mumps outbreak, they should be given 1 dose of MMR vaccine.

Because rubella during pregnancy can have dire consequences for the fetus (eg, miscarriage, multiple birth defects), all women of childbearing age, regardless of birth year, should be screened for rubella immunity. If there is no evidence of immunity, women who are not pregnant should be vaccinated. Pregnant patients who do not have evidence of immunity should be vaccinated when pregnancy is completed and before they are discharged from the health care facility.

Contraindications for the MMR vaccine include:

• A severe allergic reaction (eg, anaphylaxis) after a previous dose or to a vaccine component (ie, anaphylaxis and not delayed hypersensitivity to neomycin, anaphylaxis to gelatin)

• Known severe primary or acquired immunodeficiency (eg, due to leukemia, lymphomas, solid tumors, tumors that affect bone marrow or the lymphatic system, advanced HIV infection, treatment with chemotherapy, or long-term use of immunosuppressants)

• Pregnancy (vaccination is postponed until pregnancy is completed)

• Family history of first-degree relatives (parents or siblings) with congenital hereditary immunodeficiency, unless the vaccine recipient is known to be immunocompetent

HIV infection is a contraindication only if immunocompromise is severe (CDC immunologic category 3 with CD4 < 15% or CD4 count < 200 cells/mcL). If immunocompromise is not severe, the risk of wild measles (naturally occurring disease strains) outweighs the risk of acquiring measles from the live vaccine.

Women who have been vaccinated should avoid becoming pregnant for ≥ 28 days afterward. The viruses in the vaccine may be capable of infecting a fetus during early pregnancy. The vaccine does not cause congenital rubella syndrome, but risk of fetal damage is theoretically possible.

Precautions with the MMR vaccine include:

• Moderate or severe acute illness with or without fever (vaccination is postponed until illness resolves)

• Recent (within 11 months) treatment with blood products that contain antibody (specific interval depends on the product)

• History of thrombocytopenia or thrombocytopenic purpura

If a person is infected with Mycobacterium tuberculosis, MMR vaccine and possibly MMRV vaccine may temporarily suppress the response to tuberculin or interferon-gamma release assay testing. Thus, if needed, these tests can be performed before or at the same time as vaccination. If people have already been vaccinated, testing should be postponed for 4 to 6 weeks after vaccination.

The MMR vaccine dose is 0.5 mL subcutaneous.

The MMR vaccine is routinely administered to children in 2 doses: one at age 12 to 15 months and one at age 4 to 6 years.

The MMR vaccine causes a mild or inapparent, noncommunicable infection. Symptoms include fever > 38° C, sometimes followed by a rash. Rare central nervous system adverse effects include aseptic meningitis (1 to 10/million doses) and encephalitis (< 1/million doses). The vaccine is also associated with a small risk of febrile seizures (1/3,000 doses) and thrombotic thrombocytopenic purpura (1/30,000 doses). Anaphylaxis is rare (1).

Occasionally, the rubella component causes transient, self-limiting arthralgia and arthritis in women (2).

The vaccine does not cause autism spectrum disorder (see Measles-Mumps-Rubella (MMR) Vaccine and Vaccine Safety).

For more information about adverse effects of these vaccines, refer to the prescribing information.

The following English-language resources may be useful. Please note that The Manual is not responsible for the content of these resources.

1. Advisory Committee on Immunization Practices (ACIP): ACIP Recommendations: Measles, Mumps and Rubella (MMR) Vaccine

2. Centers for Disease Control and Prevention (CDC): Measles, Mumps, and Rubella

3. ACIP: Changes in the 2025 Adult Immunization Schedule

4. ACIP: Changes in the 2025 Child and Adolescent Immunization Schedule

5. European Centre for Disease Prevention and Control (ECDC): Measles: Recommended vaccinations

6. ECDC: Mumps: Recommended vaccinations

7. ECDC: Rubella: Recommended vaccinations