Is there anything that can be done for unvaccinated people who have already been exposed to measles, mumps, or rubella?

Measles vaccine, given as MMR, may be effective if given within the first 3 days (72 hours) after exposure to measles. Immune globulin may be effective for as long as 6 days after exposure. Postexposure prophylaxis with MMR vaccine does not prevent or alter the clinical severity of mumps or rubella. However, if the exposed person does not have evidence of mumps or rubella immunity they should be vaccinated since not all exposures result in infection.