1. Department of Community Health Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya
2. Department of Global Health University of Washington Seattle WA USA
3. Center for Clinical Research Kenya Medical Research Institute Nairobi Kenya
4. Center for Microbiology Research Kenya Medical Research Institute Nairobi Kenya
5. Department of Epidemiology University of Washington Seattle WA USA
6. Department of Medicine University of Washington Seattle WA USA