Aim: To investigate the prevalence and causes of optic neuropathy, reported as epidemic in 1997, among secondary school students in Dar es Salaam, Tanzania.
Patients and methods: 10,892 first year students from 63 secondary schools within 30km from the base hospital were interviewed and had a visual acuity screening test. Students failing the 6/12 - line in either eye were defined as having ‘poor eyesight’ and referred to the base hospital where an optometrist re-tested visual acuity and refracted them. An ophthalmologist examined students with visual acuities of 6/12 or worse in either eye and visual impairment was defined as VA ofworse than 6/12 with best correction. Associations between optic neuropathy, socio-economic status and educational results were investigated.
Results: Students ages ranged from 12-22 years , mean 15.2 years and 50.6% were male. The prevalence of optic neuropathy was 0.3% (sd=0.051). The condition affected older students and was associated with the family having fewer economic possessions (car, computer,TV). Optic neuropathy accounted for 19/33 (58%) of bilateral visual impairment cases. No effect of the disease on educational performance was identified.
Conclusion: Optic neuropathy remains a significant problem in this population and can now be termed endemic rather than epidemic.