BABESIA DIVERGENS - AN ELISA WITH SOLUBLE PARASITE ANTIGEN FOR MONITORING THE EPIDEMIOLOGY OF BOVINE BABESIOSIS

An enzyme linked immunosorbent essay (ELISA) for bovine babesiosis cau sed by Babesia divergens was developed to analyse the evolution of the serological status of cattle living in on enzootic area. The antigen used was a soluble extract of B. divergens obtained from in vitro cult ure. Specificity, evaluated with negative sera, was 96,6%. The ELISA w as compared to indirect immuno-fluorescence analysis (IFA) on naturall y or experimentally infected animals It appeared that IFA was positive for al least seven or eight weeks; on the contrary, B. divergens-spec ific antibodies were only transitorily detected by ELISA. Furthermore, the ELISA was more sensitive than the IFA for the detection of post-i nfection antibody increases, particularly when infection-pressure was tow. These results suggest that IFA and ELISA could be complementary t oots in epidemiological surveys; indeed, this ELISA could be the most efficient tool io detect new infections in cohort monitoring.