1. Department of Radiology, Children’s Hospital of Philadelphia, 3401 Civic Center Blvd, Philadelphia, PA 19104, USA
2. Perelman School of Medicine, The University of Pennsylvania, Philadelphia, PA 19104, USA
3. Division of Pediatric Global Health, Massachusetts General Hospital, Boston, MA 02115, USA
4. Botswana Harvard Health Partnership, Gaborone Private Bag BO 320, Botswana
5. Ministry of Health, Gaborone Private Bag BO 0038, Botswana
6. Department of Internal Medicine and Pediatrics, Massachusetts General Hospital, Boston, MA 02114, USA
7. Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA