Epidemic of Bilateral Optic Neuropathy in Dar es Salaam, Tanzania

Abstract

A community survey was conducted in Dar es Salaam, Tanzania, to determine the magnitude of an epidemic of bilateral optic neuropathy. Stratified simple random sampling was used to select 1078 respondents 10-39 years of age (the high-risk age group) from the city's 21 residential areas. Of the 927 respondents who were examined for signs of optic disease, 22 cases (2.4% prevalence) were detected. Hearing loss was reported by 7 affected individuals, and 16 men and women had symptoms of peripheral neuropathy (numbness and/or burning in the legs). Breast feeding was a strong risk factor. There were 7 cases among the 35 female respondents who were breast feeding (20%) compared with 6 cases among the 375 women of reproductive age who were not breast feeding (1.6%). Extrapolation of these findings suggests that 40,000 persons are currently affected with optic neuropathy in Dar es Salaam. Further investigations are needed to determine the cause of this epidemic and appropriate intervention and treatment strategies.