Development and evaluation of an antigen detection dipstick assay for the diagnosis of human onchocerciasis

Trop Med Int Health. 2005 Mar;10(3):228-33. doi: 10.1111/j.1365-3156.2004.01384.x.

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.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Helminth / analysis*
  • Antigens, Helminth / urine
  • Cameroon / epidemiology
  • Drug Storage / methods
  • Endemic Diseases
  • Female
  • Humans
  • Male
  • Onchocerca volvulus / immunology*
  • Onchocerciasis / diagnosis*
  • Onchocerciasis / epidemiology
  • Prevalence
  • Reagent Strips*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Skin / parasitology
  • Specimen Handling / methods
  • Tears / immunology

Substances

  • Antigens, Helminth
  • Reagent Strips