1. Infectious Diseases Division, icddr,b, Dhaka, Bangladesh
2. Nutrition and Clinical Services Division, icddr,b, Dhaka, Bangladesh
3. Center for Vaccine Innovation and Access, PATH, Washington, DC, USA
4. Laboratory Sciences and Services Division, icddr,b, Dhaka, Bangladesh
5. Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
6. Bacterial Diseases Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA