1. Sudan National Trachoma Control Programme, Khartoum, Sudan
2. The Carter Center, Khartoum, Sudan
3. Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
4. Taskforce for Global Health, Atlanta, Georgia, USA
5. Sightsavers, Haywards Heath, UK
6. Sightsavers, Addis Ababa, Ethiopia
7. Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland