My research focuses on the pathogenesis, prevention, and treatment of HIV and tuberculosis in resource poor settings including Haiti and Tanzania. The training of United States and international physician scientists is an integral part of my research activity. 

HIV research initially focused upon treatment and prophylaxis of opportunistic infections and then transitioned to studies of antiretroviral therapy (ART). I conducted the first large trial of ART in a developing country. This study of the first one thousand patients with AIDS treated with ART in Haiti demonstrated treatment outcomes comparable to those achieved in the United States and provided rigorous scientific evidence in support of international efforts to make ART available to AIDS patients worldwide. I was also Project Director of a randomized clinical trial that demonstrated that early ART decreases mortality four-fold and decreases tuberculosis incidence by two-fold. This study prompted the World Health Organization to change international HIV treatment guidelines. I have also conducted HIV prevention trials including studies of HIV vaccines and strategies to increase male circumcision uptake. I am currently conducting research to optimize care for HIV-infected adolescents in Haiti. I am also conducting studies in Tanzania on the interactions between schistosomiasis and HIV and on the pathogenesis of HIV induced cardiovascular disease.  

Tuberculosis research includes clinical trials to optimize treatment of both latent and active TB with a focus on HIV co-infected patients. I conducted a randomized clinical trial in HIV infected adults demonstrating that, after the successful treatment of tuberculosis, post-treatment isoniazid prophylaxis decreased the risk of TB recurrence 5-fold. Current translational studies aim to understand the persistence of M. tuberculosis in the human host and to develop new drugs that kill non-replicating mycobacteria. This includes studies of the efficacy of new drug candidates for treatment of M. tuberculosis. 

I have also conducted empirical studies to inform ethical guidelines for the conduct of research in resource poor settings and to examine the ability of illiterate research volunteers in Haiti to understand the consent form and provide voluntary consent. Further studies established educational strategies to improve comprehension and assure voluntary participation.