The role of the World Health Organization in the prevention of blindness.
D001766:Blindness / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D009855:Onchocerciasis / Q000150:complications; D014141:Trachoma / Q000150:complications; D014944:World Health Organization; D014985:Xerophthalmia / Q000150:complications