1. Department of Medicine, San Francisco General Hospital, University of California, San Francisco, San Francisco, CA 94110, USA.
2. Infectious Diseases Research Collaboration, P.O. Box 7475, Kampala, Uganda.
3. Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
4. Department of Medicine, Makerere University College of Health Sciences, P.O. Box 7051, Kampala, Uganda.
5. Department of Pediatrics, University of California, San Francisco, San Francisco, CA 94110, USA.