From the Guidelines
During a measles outbreak, immediate vaccination with the MMR vaccine is crucial for unvaccinated individuals to prevent further transmission and establish herd immunity. The MMR vaccine is the primary preventive measure, with two doses recommended for complete protection 1. For children, the first dose should be given at 12-15 months and the second at 4-6 years of age. However, during outbreaks, children as young as 6 months may receive an early dose, though they'll still need the regular two-dose series later.
Key Considerations
- For unvaccinated adults or those without evidence of immunity, at least one dose of MMR is recommended 1.
- Post-exposure prophylaxis with MMR vaccine can be effective if given within 72 hours of exposure, as stated in the guidelines from the Advisory Committee on Immunization Practices (ACIP) 1.
- Immune globulin can be administered within 6 days for high-risk individuals who cannot receive the vaccine.
High-Risk Groups
- Adults born during or after 1957 should receive 1 or more doses of MMR unless they have a medical contraindication, documentation of 1 or more doses, history of measles based on health care provider diagnosis, or laboratory evidence of immunity 1.
- A second dose of MMR is recommended for adults who have been recently exposed to measles or are in an outbreak setting, have been vaccinated previously with killed measles vaccine, have been vaccinated with an unknown type of measles vaccine during 1963–1967, are students in postsecondary educational institutions, work in a health care facility, or plan to travel internationally 1.
From the Research
Measles Outbreak and Immunization Protocol
- The Advisory Committee on Immunization Practices (ACIP) recommends 2 doses of MMR vaccine routinely for children, with the first dose administered at age 12 through 15 months and the second dose administered at age 4 through 6 years before school entry 2.
- For adults at high risk for exposure and transmission, 2 doses of MMR vaccine are recommended, while 1 dose is recommended for other adults aged ≥18 years 2.
- The National Advisory Committee on Immunization (NACI) recommends that susceptible immunocompetent individuals six months of age and older, who are exposed to measles and who have no contraindications, be given measles-mumps-rubella (MMR) vaccine within 72 hours of the exposure 3.
- For susceptible infants younger than six months of age, NACI recommends intramuscular immunoglobulin (IMIg) at a concentration of 0.5 mL/kg, to a maximum dose of 15 mL administered over multiple injection sites, if injection volume is not a major concern 3.
- The German Standing Committee on Vaccination (STIKO) recommends a single intravenous administration of immunoglobulins (400 mg/kg body weight) as soon as possible, preferably within six days, after exposure to measles, specifically for infants aged <6 months, susceptible pregnant women, and immunocompromised patients 4.
Post-Exposure Prophylaxis
- A study found that the effectiveness of MMR post-exposure prophylaxis (PEP) was 83.4%, while the effectiveness of immune globulin (IG) PEP was 100% 5.
- Another study found that the effectiveness of IVIG PEP in infants was 99.3% (CI 95%: 88.7-100%) 6.
- The use of IVIG as PEP against measles in infants has been shown to be safe and effective, with no serious adverse events reported 6.
Special Populations
- The ACIP recommends that all persons aged ≥12 months with HIV infection who do not have evidence of current severe immunosuppression should receive 2 doses of MMR vaccine 2.
- The NACI recommends that susceptible contacts who are pregnant or immunocompromised should receive IMIg at a concentration of 0.5 mL/kg, if injection volume is not a concern, or intravenous immunoglobulin (IVIg) at a dose of 400 mg/kg 3.