1. Muhimbili University of Health and Allied Sciences (MUHAS); P.O. Box 65001 Dar-es-Salaam Tanzania
2. University of San Francisco, California (UCSF); 505 Parnassus Ave. San Francisco CA 94143 United States
3. University of Nebraska Medical Center (UNMC), 982162 Nebraska Medical Center; Omaha Nebraska 68198-2162 United States
4. University of Abuja Teaching Hospital; Gwagwalada, P.M.B 228 Abuja Nigeria