HIV and malaria are two of the most important infectious diseases in sub-Saharan Africa. By 2000, over 25 million children and adults were living with HIV/AIDS, and 16 million people had died of the disease. Malaria is also of great importance in Africa, where over 90% of the 500 million annual cases and 2.7 million annual deaths occur primarily in children under the age of 5. Any interaction between these two diseases is of tremendous public health importance; however, data in this area, especially information on the relevance of HIV and malaria coinfection, are limited. Little is known about HIV infection's effects on antimalarial therapy, the effects of anti-HIV treatment on malaria incidence and treatment outcomes, and the effect of malaria on HIV disease progression. This study will examine HIV infected children in Uganda and evaluate these relationships between HIV and malaria.

This study will last 4 years. All participants will receive TMP/SMX as prophylaxis for malaria throughout this study. Children will be treated for all episodes of uncomplicated malaria with amodiaquine and artesunate; this treatment for malaria will be provided. Antiretroviral treatment for HIV, if deemed necessary by the study physician, will not be provided through this study. In the case of missed scheduled visits at the clinic, children and their parents or guardians will be visited at home by study staff, who will then bring the children and their parents and guardians to the clinic for their appointments.

Parents or guardians will be asked to bring children to the study clinic for all medical care. Unless instructed otherwise, the study clinic should be the only place where children in this study receive care and medications for the duration of the study. At each study visit for a new illness, children who have a temperature of 38 C (100.4 F) or greater, report having a fever in the 24 hours prior to the visit, or have suspected malaria will have their blood collected to check for malaria. If the blood is negative for malaria, the child will be treated with standard of care for the non-malaria illness in the Mulago Hospital complex.

If the blood is positive for malaria, the child will be classified as having either uncomplicated or complicated malaria. In cases of uncomplicated malaria, children will undergo medical history, a physical exam, and additional blood collection on the day of diagnosis (Day 0). Doses of amodiaquine and artesunate will be given once a day for 3 days in the study clinic by a study nurse, who will directly observe the child taking the medication. Study visits associated with uncomplicated malaria will occur on Days 1, 2, 3, 7, 14, 28, and any other day when the child feels ill; a physical exam and blood collection to check for malaria will occur at all visits. In cases of complicated malaria, children will be treated with quinine and will be referred to the Acute Care Unit of the Mulago Hospital complex.

Regardless of health during the course of the study, children will need to return to the clinic every 30 days to undergo a physical exam and blood collection to check for malaria. If malaria is found, children will undergo the 14-day standardized follow-up period as described above. At least every 3 months, additional blood collection will occur to determine HIV viral load, liver and kidney function, and immune parameters.

As of 07/01/08, all study participants with malaria will receive standard of care treatment through the Pediatric Infectious Disease Clinic. No treatment will be provided by the study.