Myopia in Melanesian school children in Vanuatu.

Visual acuity, refraction, and the components of refraction were measured in 788 Melanesian children in the South Pacific island nation of Vanuatu. Of the 788 children, 97.2% were found to have uncorrected visual acuity of 6/6, 96.8% were found to have a spherical equivalent refraction between -0.25 and +1.00 D, 2.9% were found to have myopia of 0.50 or more, 0.25% were found to have hyperopia of 1.25 D or more, and 0.25% were found to have refractive astigmatism of 1.25 D or more. The low prevalence of ametropia may be considered to be due mainly to genetic factors; however, the possibility of environmental factors cannot be ruled out.