Although the vaccine has been withheld from individuals with a history of hypersensitivity to eggs, it has been found to be safe in these circumstances. Persons with severe neomycin or gelatin allergies should not receive the vaccine, because it contains small amounts of neomycin and gelatin. Patients with moderate or severe upper respiratory tract infections or febrile illnesses should recover before receiving the vaccine. Measles vaccine may protect susceptible individuals who have been exposed to measles if it is given within 72 hours after exposure. Measles vaccination appears to be safe for HIV-infected individuals, but a case of measles pneumonitis has been reported in a patient with immunosuppression from advanced AIDS who was not receiving antiretroviral therapy.
Vaccine failures are much more common.
Because natural measles can cause severe pneumonia and death in these persons, immune globulin should be considered for postexposure prophylaxis in HIV-infected individuals who are exposed to measles, regardless of their immunization status. The two-dose measles immunization schedule and the renewed effort to deliver the vaccine to susceptible individuals have been very effective. In the United States, reported cases of measles fell to a historic low in 1993, but a fourfold increase in 1994 underlines the need for continued vigilance. In Finland, indigenous measles, mumps, and rubella have been eliminated by a two-dose vaccination program, and substantial progress is being made in the Americas. Reported cases of mumps in the United States have declined by more than 99 percent to about 1,600 cases annually.