Monoclonal antibody based competitive ELISA for the detection of specific antibodies against Coxiella burnetii in sera from different animal species.

A competitive ELISA system for the detection of antibodies against Coxiella (C.) burnetii in cattle, sheep, goats, horses and humans is described. The ELISA is based on a biotinylated monoclonal antibody with specificity for C. burnetii lipopolysaccharide in combination with streptavidin peroxidase. For evaluation and statistical analysis, 413 sera from cattle, sheep, goats, horses and humans were tested in parallel in the indirect immunofluorescence test (IFT). Furthermore, a total of 448 bovine and human sera were also tested with an indirect ELISA and 47 sheep sera were investigated using the commercially available "Ridascreen AK EIA". Sensitivity and specificity values for the competitive ELISA described and determined with the aid of the indirect immunofluorescence test (IFT) as reference were: cattle, 88% and 89%; sheep, 100% and 93%, goat, 82% and 96%, horse 100% and 93%, and man 42% and 96%, respectively.