The prevention of blindness.
D000208:Acute Disease; D001766:Blindness / Q000209:etiology / Q000517:prevention & control*; D003231:Conjunctivitis / Q000150:complications; D006281:Health Occupations / Q000193:education; D006801:Humans; D009855:Onchocerciasis / Q000150:complications; D014141:Trachoma / Q000150:complications; D014985:Xerophthalmia / Q000150:complications