Immunodiagnosis of parasitic zoonoses: comparative efficacy of three immunofluorescence tests using antigens purified by affinity chromatography.

Three immunofluorescent antibody assays were developed during this study: the direct (DFAT) and indirect (IFAT) fluorescent antibody tests using frozen worm sections, and the cyanogen bromide indirect fluorescent antibody test (CNBr-IFAT) using helminth antigens purified by affinity chromatography bound on to commercially prepared CNBr-Sepharose 4B beads. Purified antigens used in the CNBr-IFAT gave greater specificity and sensitivity than either the DFAT or IFAT. Dirofilaria immitis, Toxocara canis, Angiostrongylus cantonensis and Ascaris lumbricoides infections were studied in natural and zoonotic hosts and in rabbits immunized with antigens prepared from these parasites. In addition, a serological survey of Aboriginal Australians from Queensland was made.