Infections continue to be major causes of morbidity and mortality worldwide. Perinatal complications, including fetal loss are also major problems in many developing countries, even in settings that provide adequate prenatal care. The risks of low birth weight and preterm birth are high and these outcomes are major predictors of child health and survival in the first year of life and beyond. Our group focuses on examining the role of nutritional and other factors in the etiology of adverse health outcomes among populations in developing countries, with emphasis on infectious and perinatal outcomes among mothers and children.
Using data from a large population-based, placebo-controlled trial in the Sudan, we have determined that periodic large doses of vitamin A may not have an effect on child survival and infections in certain populations. This result is in contrast to large protective relationships with dietary vitamin A intake observed in the same study population. We have carried out comprehensive reviews of the literature on the role of vitamin A and other micronutrients on various infectious diseases.
In collaboration with colleagues at Muhimbili University in Tanzania, we are implementing several large randomized controlled trials to examine the efficacy of various micronutrient supplements on the incidence and severity of a number of infectious diseases including pneumonia, diarrhea, tuberculosis, and HIV infection. We have recently completed a trial on effect of vitamin A supplements during the acute phase of infection among children who were admitted to the hospital with pneumonia, and on the incidence and severity of respiratory, diarrheal, and other infections in the 12 months after discharge from the hospital. We are carrying out another large clinical trial in Tanzania to determine the effect of vitamin supplements on the risks of adverse birth outcomes and perinatal transmission of HIV and the rate of progression of disease among HIV-positive women. We reported that prenatal multivitamin supplementation of HIV-infected women resulted in large and significant reductions in the risk of fetal loss, low birth weight , and severe prematurity. We are currently ascertaining whether these findings are generalizable to the larger population of HIV-negative women.
Our group is also active in examining the efficacy of various interventions in the prevention of HIV infection in developing countries. As part of the NIH-funded HIV Prevention Trials Network, we are engaged in examining strategies for reducing perinatal and heterosexual transmission of infection. Using data and specimens collected in all our trials, we are exploring basic questions on the virology and immunology of infectious endpoints.