1. Division of Foodborne and Waterborne and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia;
2. Tanzania Field Epidemiology and Laboratory Training Program, Dar es Salaam, Tanzania;
3. Division of Global Health Protection, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia;
4. Ministry of Health, Community Development, Gender, Elderly and Children, United Republic of Tanzania, Dar es Salaam, Tanzania