EVALUATION OF AN ENZYME-LINKED-IMMUNOSORBENT-ASSAY FOR DETECTION OF EPERYTHROZOON SUIS ANTIBODIES IN SWINE

An ELISA was developed and tested to detect antibodies to Eperythrozoon suis in swine. Results were compared with those of the indirect hemagglutination (IHA) test. Antigen isolated from swine heavily infected with E suis was used for both tests. Comparison of the ELISA with the IHA test revealed a significant (P < 0.001) correlation between results. Of 114 samples obtained from 9 swine infected with E suis, 87.7% were seropositive (titer greater-than-or-equal-to 200) via the ELISA, and 80.7% were seropositive (titer greater-than-or-equal-to 20) via the IHA test. The sensitivity of the ELISA was greater than that of the IHA test. All blood samples obtained from specific-pathogen-free swine tested negative for E suis antibody. Cross-reactions were not observed between E suis antigen and antisera against various swine and cattle disease agents using ELISA. We concluded that the ELISA may be used for rapid and effective diagnosis of infection with E suis in swine.