A prospective study was conducted in slum children to determine the incidence of post-measles corneal disease and to clarify its relationship with nutritional status. A total of 318 cases of measles were identified over a period of 15 mo; maximum incidence was observed for children between 1-2 yr. Most of the children showed weight loss and serum proteins decrease during the acute stage of measles. Corneal lesions were observed in 3% of the children, and the lesions responded well to treatment. Serum vitamin A and RBP levels were significantly depressed during the acute stage of measles but were restored to normal 8 wk after recovery. There were no significant differences in the serum levels for those with and without eye lesions, which suggests that these lesions may not be mediated simply through the effect of infection on serum concentration of vitamin A.