1. Division of Foodborne, Waterborne, and Environmental Diseases, US Centers for Disease Control and Prevention , Atlanta, Georgia , USA
2. Kenya Medical Research Institute, Center for Global Health Research , Kisumu , Kenya
3. Center for Vaccine Development and Global Health, University of Maryland School of Medicine , Baltimore, Maryland , USA
4. Department of Medicine, University of Maryland School of Medicine , Baltimore, Maryland , USA
5. Department of Pediatrics, University of Maryland School of Medicine , Baltimore, Maryland , USA
6. Medical Research Council Unit, The Gambia at the London School of Hygiene and Tropical Medicine ; Banjul , The Gambia
7. Centre pour le Développement des Vaccins du Mali (CVD-Mali) , Bamako , Mali
8. Division of Global Health Protection, US Centers for Disease Control and Prevention , Nairobi , Kenya
9. Division of Infectious Diseases and International Health, University of Virginia , Charlottesville, Virginia , USA
10. School of Public Health at Qingdao University , Qingdao , China