Early diagnosis of human fascioliasis by the detection of copro-antigens using counterimmunoelectrophoresis.

We have reported the use of partially purified Fasciola gigantica worm antigens (peaks II and III separated by Sephadex G-200) in counterimmunoelectrophoresis (CIEP) for the specific and early detection of antibodies in sera of fascioliasis patients. In the present study, we report the use of hyperimmune serum from rabbits immunized with these partially purified worm antigens in CIEP for the detection of parasite antigens in saline extracts of patients' stools. This test was conducted on stool specimens from 144 patients with systemic or intestinal parasitic infections, 5 from persons with spurious Fasciola infections, and 10 from healthy negative controls. All saline extracts from fascioliasis patients developed 2-5 precipitin bands. No precipitin band developed with stool extracts of patients with spurious Fasciola infection or other parasitic infections, or from negative controls. This assay proved to be simple, rapid, sensitive, and specific for the diagnosis of early as well as established fascioliasis infections.