Table 1

Causes of blindness from some recent population based studies of all age groups in developing countries

CountryPercentage prevalence of blindness
CataractRefractive error TrachomaOnchocerciasis
China28 0.18NA0.05nil
Lebanon29 0.250.08nilnil
South Africa30 0.59NAnilnil
India14 0.610.20nilnil
Mali25 1.17nil0.21nil
Central African Republic26 0.36nil0.101.61
Other corneal opacity Glaucoma Others Total
South Africa30
Central African Republic26 nil0.050.082.20
  • Blindness defined as visual acuity <3/60 in the better eye. Best corrected visual acuity used to define blindness in studies from China and South Africa, and presenting visual acuity used in the other studies.

  • Refractive error blindness includes aphakia. The study from India also includes refractive error related amblyopia.

  • Other corneal opacities are mainly vitamin A deficiency, infectious keratitis, and use of harmful traditional eye medicines.

  • NA is not applicable as these two studies used best corrected visual acuity to define blindness.