title: Development and evaluation of an antigen detection dipstick assay for the diagnosis of human onchocerciasis.
abstract: To improve on the diagnosis of onchocerciasis, especially light infections, we developed and evaluated an oncho-dipstick test based on the detection of Onchocerca volvulus specific antigens in urine and tears. The test was able to detect as little as 25 ng/ml of parasite specific antigens in samples and took as little as 3 h. Evaluation of the assay on 456 residents of an onchocerciasis hyperendermic area in Cameroon resulted in 408 (89.5%) positives in urine and 374 (82%) positives in tears. The prevalence of onchocerciasis in the study area, as determined by Rapid Epidemiological Mapping of Onchocerciasis (REMO) and skin snip methods, was 52 and 36.8%, respectively. The sensitivity of the oncho-dipstick assay was 100% in urine and 92% in tears; its specificity was 100% in both. Concordance between urine and tear test results from the same individuals was 87%. The test strips were sufficiently reactive when left at room temperature for up to 8 months. The test would be useful for laboratory diagnosis of onchocerciasis in low transmission zones and to ascertain successful treatment of patients in experimental drug studies.
authors.affiliation: IMPM/MINREST, Yaoundé, Cameroon. layong05@yahoo.co.uk
authors.forename: L S
authors.initials: LS
authors.lastname: Ayong
authors.forename: C B
authors.initials: CB
authors.lastname: Tume
authors.forename: F E
authors.initials: FE
authors.lastname: Wembe
authors.forename: G
authors.initials: G
authors.lastname: Simo
authors.forename: T
authors.initials: T
authors.lastname: Asonganyi
authors.forename: G
authors.initials: G
authors.lastname: Lando
authors.forename: J L
authors.initials: JL
authors.lastname: Ngu
mesh_terms: D000818:Animals; D000947:Antigens, Helminth / Q000032:analysis* / Q000652:urine; D002163:Cameroon / Q000453:epidemiology; D004356:Drug Storage / Q000379:methods; D019353:Endemic Diseases; D005260:Female; D006801:Humans; D008297:Male; D017181:Onchocerca volvulus / Q000276:immunology*; D009855:Onchocerciasis / Q000175:diagnosis* / Q000453:epidemiology; D015995:Prevalence; D011934:Reagent Strips; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012867:Skin / Q000469:parasitology; D013048:Specimen Handling / Q000379:methods; D013666:Tears / Q000276:immunology
chemical_list: D000947:Antigens, Helminth; D011934:Reagent Strips