Purpose: The aim of the study was to determine the prevalence and causes of eye diseases and visual impairment in students in the Ilesa East local government area of Osun state, Nigeria.

Methods: A cross-sectional survey that utilised a multistage random sampling method to select 1,144 primary and secondary school students.

Results: A total of 1,144 students (504 males and 640 females) were involved in the study. Their ages ranged from 4 to 24 years. The majority (97.8%) of them were below 18 years of age. A total of 177 (15.5%) of the school children were found to have eye diseases. The major ocular disorders were in the following order: conjunctiva 91 (51.4%), refractive error 66 (37.3%), lid 7 (4.0%), corneal, including staphyloma and keratoconus 5 (2.8%) and then others. These included conjunctival diseases 91 (8%) constituted mainly by allergic/vernal conjunctivitis 85 (7.4%), refractive error 66 (5.8%), lid disorders 6 (0.6%), squint 3 (0.3%), corneal scarring 3 (0.3%) and cataract 2 (0.2%). A total of 15 students were visually impaired, with a prevalence of 1.26%. Only two students were blind, with a prevalence of 0.17%. Causes of visual impairment were refractive error 10 (0.87%), bilateral immature cataract 1 (0.08%), corneal opacities 2 (0.2%), amblyopia leading to squint 1 (0.08%) and cataract 1 (0.08%). The causes of blindness in students were bilateral corneal scars presumed to be due to vitamin A deficiency in one (0.08%) student and complicated bilateral keratoconus with complicated vernal ulcers in another (0.08%).

Conclusions: Eye diseases are common amongst Nigerian students. Eye examination for all new intakes and regular screening in both public and private primary and secondary schools is advocated. Wearing of corrective glasses should be emphasised for children with refractive error. Causes of blindness and visual impairment in children attending regular schools in Nigeria were avoidable.