title: Longitudinal study of onchocerciasis in Bebeka-Ethiopia.
abstract: This paper describes the morbidity, intensity and prevalence of onchocerciasis in an endemic area of Ethiopia, using a cross-sectional study (n = 425) and a longitudinal cohort study (n = 98). During the study period (February-October 1987), the increase in intensity and in number of cases with dermal lesions was highly significant (p < 0.005) when compared with the increase in the microfilarial positivity rate (p < 0.1). Since the serial increase in dermatologic problems was not directly correlated with an increase in O. volvulus microfilarial prevalence or intensity, it is suggested that hyper-sensitivity responses to repeated Simulium bites might exacerbate onchocercal dermal lesions. The controversy concerning Simulium bites as a cause of lesions mimicking those due to O. volvulus parasites is discussed.
authors.affiliation: National Research Institute of Health, Addis Abeba, Ethiopia.
authors.forename: S
authors.initials: S
authors.lastname: Taticheff
authors.forename: J F
authors.initials: JF
authors.lastname: Williams
authors.forename: W
authors.initials: W
authors.lastname: Workneh
mesh_terms: D000293:Adolescent; D000328:Adult; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D002980:Climate; D003430:Cross-Sectional Studies; D005002:Ethiopia / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009855:Onchocerciasis / Q000453:epidemiology* / Q000276:immunology / Q000469:parasitology / Q000473:pathology / Q000517:prevention & control; D011159:Population Surveillance; D015995:Prevalence; D012621:Seasons; D012720:Severity of Illness Index