Post-Exposure Prophylaxis for Measles

Introduction to Post-Exposure Management

The Centers for Disease Control and Prevention recommends administering MMR vaccine within 72 hours to susceptible persons ≥6 months of age, except pregnant women and immunocompromised patients, for measles exposure 1, 2
For individuals beyond 72 hours but within 6 days of exposure, immune globulin is the preferred intervention instead of MMR vaccine 1, 2, 4

The American Academy of Pediatrics and the Centers for Disease Control and Prevention recommend MMR vaccine as the preferred intervention for most susceptible individuals within 72 hours of exposure, with eligible recipients being persons ≥6 months of age without contraindications 1, 2
MMR vaccine is preferred in settings such as day care facilities, schools, colleges, health-care facilities, and household contacts 1
Key contraindications for post-exposure MMR include pregnant women, immunocompromised persons, and infants <6 months of age 1, 2, 3
For individuals who receive immune globulin, a standard dose of 0.25 mL/kg IM is recommended for immunocompetent persons, while a higher dose of 0.5 mL/kg IM is recommended for immunocompromised persons 1, 3, 4

The Centers for Disease Control and Prevention recommends that infants vaccinated before 12 months must be revaccinated with two doses of MMR starting at ≥12 months, separated by at least 28 days 1, 2
Immunocompromised patients should receive IG prophylaxis regardless of vaccination status, and the higher dose of 0.5 mL/kg should be used 1, 2, 3
Patients receiving IGIV therapy should receive a standard dose of 100-400 mg/kg to prevent measles if exposure occurs within 3 weeks of IGIV administration 1, 2

Any person who receives IG must subsequently receive MMR vaccine 5-6 months later, if ≥12 months old and vaccine not otherwise contraindicated, to ensure long-term protection 1, 4, 5
This delay is necessary because passively acquired antibodies from IG interfere with vaccine response 1, 4, 5

The Centers for Disease Control and Prevention advises against using IG to control measles outbreaks in the general population, and instead recommends using MMR vaccine 1
Household contacts should not be assumed to be diagnosed within 72 hours, making IG a more practical choice for this group 1
Immunocompromised patients should not receive the standard IG dose, but rather the higher dose of 0.5 mL/kg 1, 3
MMR vaccine should not be given to immunocompromised patients for post-exposure prophylaxis, even within 72 hours, as they require IG instead 1, 2, 3