1. London School of Hygiene and Tropical Medicine, London, EnglandInternational Centre for Diarrheal Disease Research, Dhaka, BangladeshThese authors contributed equally to this work.
2. International Centre for Diarrheal Disease Research, Dhaka, BangladeshThese authors contributed equally to this work.
3. International Centre for Diarrheal Disease Research, Dhaka, Bangladesh
4. University of Ghana Medical School, Accra, Ghana
5. University of Virginia School of Medicine, Charlottesville, Virginia, USA
6. London School of Hygiene and Tropical Medicine, London, England