Middle ear disease and hearing impairment in northern Tanzania. A prevalence study of schoolchildren in the Moshi and Monduli districts.

A total of 854 schoolchildren from one urban and one rural district in northern Tanzania were examined for the presence of middle ear pathology and hearing loss by means of pneumotoscopy and screening audiometry (air conduction). The prevalence of chronic otitis media (COM) was 1.6%, with no difference between urban and rural children. Scarred and sclerotic tympanic membranes were found in 10.9% of urban children and in 15.1% of rural children, the difference being significant. Hearing loss within the speech frequency range in all the children studied was found in 37% of the urban children and in 18% of the rural children. However, the prevalence of hearing loss above 30 dB HL was 3% in both districts. High frequency loss was significantly more common among urban than among rural children. Undetected severe hearing impairment/deafness was found in three children in the rural district, while none was found in the urban district.