Evaluation of Quantitative and Qualitative Antibody Responses to Streptococcus Pneumoniae and Haemophilus Influenzae Type b Conjugate Vaccines Amongst HIV-1-Exposed-Infected Children That Are Receiving Vs. Those Not Receiving Antiretroviral Therapy, as Well as Among HIV-1-Exposed-Uninfected Children and HIV-1-Unexposed-Uninfected Children

HIV infected children are at high risk for invasive pneumococcal disease (IPD) caused by the bacterium Streptococcus pneumoniae. Chemoprophylaxis has been used in children with certain diseases for the prevention of IPD, but drug resistance may develop with this prevention strategy. In contrast, a vaccine to prevent IPD would have fewer negative implications on future treatment options than chemoprophylaxis. This study will evaluate the safety of and immune response to PncCV in South African HIV infected and uninfected children. This study will also evaluate the safety of and immune response to HibCV in these children.

This study will last 5.5 years. There will be 5 groups in this study. Group 1 will be HIV uninfected infants born to HIV uninfected mothers. Group 2 will be HIV infected infants in CDC Disease Category 1 who were randomly assigned to the delayed therapy arm (Arm 1) of CIPRA SA-Project 2. Group 3 will be HIV infected infants in CDC Disease Category 1 who were randomly assigned to the first early therapy arm (Arm 2) of CIPRA SA-Project 2. Group 4 will be HIV infected infants in CDC Disease Category 2 or 3 who were randomly assigned to the second early therapy arm (Arm 3) of CIPRA SA-Project 2. Group 5 will be HIV uninfected infants born to HIV infected mothers; Group 5 infants will undergo repeat HIV testing at 4 to 8 months of age, 9 to 11 months of age, and approximately 18 months of age.

There will be 13 study visits; medical history assessment, a physical examination, and blood collection will occur at each visit. At each of 3 study visits before age 24 weeks, all participants will receive an injection of PncCV and an injection of routine pediatric vaccines, including HibCV. Previously vaccinated HIV infected participants will only receive those vaccines they need to complete the South African series of routine pediatric vaccinations. Within each group, participants will be randomly assigned to receive a booster shot of either PncCV or HibCV between 64 and 76 weeks of age. Participants will also receive two measles vaccinations between 38 and 76 weeks of age. Parents or guardians will be asked to complete a diary card after each vaccination and report any adverse effects occurring within the 72 hours post-vaccination.