Childhood blindness in the West Bank and Gaza Strip: prevalence, aetiology and hereditary factors.

A study of all the schools for the blind in the West Bank and Gaza Strip was undertaken during 1991-2. Two hundred and five children had a complete ophthalmic examination. This represented 94% of all children aged 5-15 years attending schools for the blind. According to WHO categories of visual loss, 63% were blind and 21% had severe visual impairment. The main causes of blindness and severe visual loss were retinal (52%), optic atrophy (12%), glaucoma (9%) and cataract (7%). Common retinal diseases included degenerative myopia, Leber's congenital amaurosis, cone dystrophy and retinitis pigmentosa. Depending on the locality, 44-85% of these children were the product of a consanguineous marriage and a positive family history was present in 57%. The minimum prevalence of childhood blindness was estimated to be 0.32/1000 children. A reduction in the prevalence of blindness requires a reduction in consanguineous marriages, genetic counselling for affected families and public health measures to ensure early referral for management of cataract and glaucoma.