1. Paediatric Ophthalmology and Strabismus, Moorfields Eye Hospital, London, UK
2. National Institute for Health Research Biomedical Research Centre at Moorfields Eye Hospital, London, UK
3. UCL Institute of Ophthalmology, University College London, London, UK
4. Kings College, University of London, London, UK
5. Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK