Role of ELISA in early detection of Fasciola copro-antigens in experimentally infected animals.

An immunodiagnostic sandwich enzyme-linked immunosorbent assay (ELISA) was performed for the detection of F. hepatica antigens in stool sample (copro-antigens) of experimentally infected animals (mice, rats and rabbits) over a period of 18 weeks using affinity-purified polyclonal antibodies raised against the whole adult F. gigantica. The test demonstrated fascioliasis in mice earlier than in rats or rabbits (4, 6 and 7 weeks post infection respectively) by detection of copro-antigens in stool samples. In all experimentally infected models, F. hepatica copro-antigens concentration showed continuous increase and mice samples had higher antigen concentration than rats and rabbits. Sensitivity of ELISA was significantly higher in mice (83.3%) than in rats and rabbits (75% and 66.7% respectively) and its specificity showed nearly similar results to sensitivity. From the previously obtained data, it could be concluded that ELISA proved to be a rapid, easy and sensitive test for diagnosing fascioliasis by detection of F. hepatica copro-antigens earlier than routine stool examination of Fasciola eggs.