1. London School of Hygiene and Tropical Medicine, London, England2Department of Ophthalmology, University of Nairobi, Nairobi, Kenya
2. PCEA Kikuyu Eye Unit, Kikuyu, Kenya
3. Eye Department, Kitale District Hospital, Kitale, Kenya
4. Sabatia Eye Hospital, Wodanga, Kenya
5. Ophthalmology Department, Kenyatta National Hospital, Nairobi, Kenya
6. Department of Pathology, MP Shah Hospital, Nairobi, Kenya
7. UCL Institute of Ophthalmology, London, England9Moorfields Eye Hospital, London, England10St Bartholomew’s Hospital, London, England
8. London School of Hygiene and Tropical Medicine, London, England
9. London School of Hygiene and Tropical Medicine, London, England9Moorfields Eye Hospital, London, England