1. Department of Biomedical Science and Technology, Maseno University, P.O. Box 333-40105, Maseno, Kenya
2. Department of Human Pathology, School of Medicine, Moi University, P.O. Box 4606-30100, Eldoret, Kenya
3. Department of Medical Physiology, School of Medicine, Maseno University, P.O. Box 333-40105, Maseno, Kenya
4. Department of Research, USAID-AMPATH Partnership, P.O. Box 4606-30100, Eldoret, Kenya