Recommendations for the age at vaccination should balance the need to minimize the risk of morbidity and mortality with the benefit of achieving the highest seroconversion rates. Immunizing a more intact immune system at an earlier stage of HIV infection may in turn achieve better and long-lasting measles protection. This study will help define a more effective measles vaccine regimen for children diagnosed with HIV infection and will provide greater insight into the functional status of the HIV-infected children's humoral immune system.~Patients, HIV infected and uninfected, are randomized to one of two attenuated measles vaccine schedules: at 6 and 12 months of age, or at 12 months of age only. Attenuvax is administered as the month 6 vaccine and M-M-R II as the month 12 vaccine. Patients are followed for 24 months after the last vaccination.
To compare measles seroconversion rates (development of antibodies) at 13 months of age in HIV-infected and uninfected children on one of two immunization schedules: attenuated measles/mumps/rubella virus (M-M-R II) vaccine at 12 months versus attenuated measles vaccine (Attenuvax) at 6 months plus M-M-R II vaccine at 12 months.~Recommendations for the age at vaccination should balance the need to minimize the risk of morbidity and mortality with the benefit of achieving the highest seroconversion rates. Immunizing a more intact immune system at an earlier stage of HIV infection may in turn achieve better and long-lasting measles protection. This study will help define a more effective measles vaccine regimen for children diagnosed with HIV infection and will provide greater insight into the functional status of the HIV-infected children's humoral immune system.