Outbreak of louse-borne relapsing fever in Jimma, south western Ethiopia.

Some epidemiological aspects of louse-borne relapsing fever during the epidemic of 1991 in Ethiopia are described. There was male preponderance and the age ranged from two months to 58 years (mean, sd = 18.05,11.19). There was no sex differential in children. Students, soldiers and jobless contributed the majority. There were two peaks (August and March) in the seasonal pattern. About two-thirds was infested with lice and significant associations were found among adults, soldiers, ethnicity, illiterate persons and family size above seven. The household attack rate was 15.1%, the attack being higher among children. Promotion of preventive measures are recommended.