MMR Vaccine Dosage Recommendations

Standard Dosing Schedule

The Centers for Disease Control and Prevention recommends that the MMR vaccine is supplied as a lyophilized product that must be reconstituted with the accompanying diluent before administration, and after reconstitution, a single dose is approximately 0.5 mL and should be administered subcutaneously 1
The standard MMR vaccine dose is 0.5 mL administered subcutaneously, with two doses recommended for routine vaccination: the first at age 12-15 months and the second at age 4-6 years, with doses separated by at least 28 days 1, 2
For routine childhood vaccination, the recommended schedule is: first dose at 12-15 months of age and second dose at 4-6 years of age, with a minimum interval of 28 days between doses 1

For previously unvaccinated children and adolescents, two doses are required, separated by at least 28 days, as recommended by the Centers for Disease Control and Prevention 1
Adults born in 1957 or later without evidence of immunity should receive at least one dose of MMR vaccine, according to the American College of Physicians 3
Infants aged 6-11 months traveling internationally should receive a single dose before travel, and later receive two full doses on the routine schedule, with the first dose at 12-15 months, as recommended by the Centers for Disease Control and Prevention 1, 4

The Centers for Disease Control and Prevention recommends that MMR can be administered simultaneously with other vaccines at different anatomic sites 5
Live virus vaccines not administered on the same day should be separated by ≥4 weeks, as recommended by the Centers for Disease Control and Prevention 1

If immune globulin is administered, subsequent MMR vaccination should be delayed for 5-6 months after administration of standard IG, as recommended by the Centers for Disease Control and Prevention 4, 6

Almost all persons who don't respond to the first dose will respond to the second dose, according to the Centers for Disease Control and Prevention 2

The Advisory Committee on Immunization Practices (ACIP) recommends that individuals with two documented doses of MMR vaccine are considered immune, regardless of serologic testing results, and do not need a third dose 7, 8, 9
The ACIP explicitly states that for individuals who have 2 documented doses of MMR vaccine, it is not recommended to receive an additional dose of MMR vaccine if they test serologically negative or equivocal for measles, mumps, or rubella, as documented age-appropriate vaccination supersedes subsequent serologic testing results 7, 8, 9
Such persons should be considered immune based on their vaccination history alone, as the two-dose MMR schedule is designed to capture primary vaccine failures, and almost all persons who don't respond to the first dose will respond to the second dose 7, 8

The ACIP recommends that serologic testing after documented vaccination is not recommended because vaccination status is considered adequate presumptive evidence of immunity, and antibody titers can wane over time without loss of immune memory 7, 8, 9
Do not routinely order serologic testing after two documented MMR doses, as this creates unnecessary confusion when titers return low or negative, and do not revaccinate based solely on negative titers in someone with proper documentation of two MMR doses 7, 8, 9
The exception is if you're uncertain about vaccine type or timing, in which case revaccination is appropriate, according to the 1998 ACIP guidelines 10

This recommendation comes from the 2011 ACIP guidelines, which represent the authoritative U.S. guidance on immunization practices, and the guidance is consistent across multiple ACIP publications and has remained stable over time 7, 8, 9, 10, 11

The Advisory Committee on Immunization Practices (ACIP) recommends that documented age-appropriate vaccination supersedes the results of subsequent serologic testing, and healthcare personnel with 2 documented doses of MMR vaccine administered at least 28 days apart should be considered immune, regardless of negative serologic results 12
Confirm written documentation of 2 doses of live measles or MMR vaccine administered at least 28 days apart, as recommended by the ACIP 12
Such persons should be considered to have presumptive evidence of measles immunity and do not require work restrictions, according to the ACIP 12

All healthcare personnel should observe airborne precautions when caring for patients with measles, regardless of presumptive immunity status, because of the low possibility of vaccine failure, as recommended by the ACIP 12
Use respiratory protection consistent with airborne infection control (N95 respirator or equivalent), as recommended by the ACIP 12
Monitor for measles-compatible symptoms for 21 days post-exposure, as recommended by the ACIP 12
If symptoms develop, exclude from work until ≥4 days following rash onset, as recommended by the ACIP 12

MMR vaccine given within 72 hours of measles exposure may provide some protection or modify disease severity, according to the ACIP 12
However, for healthcare workers with 2 documented doses, additional vaccination is not indicated even post-exposure, as recommended by the ACIP 12
Immune globulin (IG) can be considered for post-exposure prophylaxis in truly susceptible individuals within 6 days of exposure, but not for healthcare workers with 2 documented MMR doses, as recommended by the ACIP 12