Prevalence of hearing loss among primary school children in Ethiopia

The objective of this study was to determine the prevalence of hearing loss in children attending primary schools in urban and rural Ethiopia.

A cross-sectional study was performed to determine the prevalence of hearing loss in children aged 7 to 14 years. A total of 384 children had complete examinations and were included in the study.

The prevalence of hearing loss of all types in the urban school was 6.2% using a cut-off of 40 dB Fletcher index (500-2000 Hz). The prevalence increased to 10.2 % in the same population if a cut-off of 25 dB HL FI was used. In the rural school with a cut-off of 30 dB HL the hearing prevalence was 5.9%. The proportion of conductive hearing loss was lower in the urban school and constituted 16% of all hearing losses. We estimated the proportion of conductive hearing loss in the rural school to be at least 50%. In the urban school the prevalence of sensorineural hearing loss was 5.8% while it was much lower at 1.3% and exclusively unilateral in the rural school. The degree of hearing loss according to WHO criteria was calculated only for the urban population. A prevalence of bilateral severe hearing loss (≥61 dB HL) of 0.5% and of moderate hearing loss (> 41 dB and ≤60dB HL) of 1% was found using WHO criteria.The prevalence of chronic suppurative otitis media and of dry perforations were similar between schools (2.5 to 2.7%). Otitis media was rare in this study likely due to seasonal influences and exclusion of very young children. These results are compared to similar school studies in Sub-Saharan Africa.

The prevalence of hearing loss in these two Ethiopian cohorts (rural and urban) is in agreement with the data published by WHO for Sub-Saharan Africa. While some of the variation between urban and rural populations may have been real, some of the discrepancy may have resulted from differences in acoustic testing environments. We describe these challenges in hopes of improving universal screening procedures.