First results of chronic wasting disease (CWD) surveillance in the south-eastern part of Belgium.

Chronic wasting disease (CWD) has not been reported in Europe, whereas it is considered to be enzootic in free-ranging mule deer, Rocky mountain elk and white-tailed deer in the area of Colorado, Wyoming, and Nebraska, and new foci of CWD have been detected in other parts of the United States. However, no large-scale active epidemiosurveillance of European wild cervids has been installed in Europe. In accordance with the opinion of the European Scientific Steering Committee, a preliminary (active) surveillance scheme was installed, in order to improve the knowledge of the CWD status of the Belgian free-ranging cervids (roe deer and red deer). Spleen samples (n=866) of roe deer and red deer collected in the south-eastern part of Belgium, were examined for CWD using a enzyme-linked immunosorbent assay of Bio-Rad. Afterwards, the ELISA was systematically confirmed by immunohistochemistry using three antibodies, namely R524, 2G11 and 12F10. There were no indications on the occurrence of transmissible spongiform enncephalopathy (TSE) in any of the samples. A Bayesian framework was used for the estimation of the true prevalence of CWD in south-eastern part of Belgium that was estimated to have a median value of zero with a 95% percentile value of 0.00115.