Application of the enzyme-linked immunosorbent assay (ELISA) for the diagnosis of filariasis and echinococcosis.

The Enzyme-Linked Immunosorbent Assay (ELISA) was compared with the Indirect Fluorescent Antibody Test (IFAT), the Indirect Haemagglutination Test (IHA) and Counter Immuno Electrophoresis (CIE) in the serological examination for filariasis and echinococcosis. The ELISA was the most sensitive but least specific method. The most striking phenomena were the cross-reactions observed when filariasis sera and E. granulosus hydatid fluid antigen were tested and vice versa, when echinococcosis sera were tested with D. viteae antigen. Crossreacting antibodies could be absorbed with the non-corresponding antigens. ELISA proved to be the most convenient test for the screening of large numbers of sera. For a specific diagnosis however it was nevertheless essential to test ELISA reactive sera with other methods.