Evaluation of a commercial competitive ELISA for the detection of antibodies to Rift Valley fever virus in sera of domestic ruminants in France.

This paper describes the sensitivity and specificity of a commercial competitive ELISA for the detection of antibodies to Rift Valley fever virus (RVFV) from sera of French domestic ruminants. Field samples were collected from mainland France for the known-negative sera (cattle=191, goats=119, sheep=192) and from ruminants of a French overseas territory (Mayotte) for the known-positive sera. A cut-off value of 43% was determined for all species, achieving a sensitivity and specificity of 100% and a concordance of 100% with the species-specific threshold recommended by the manufacturer. Our results demonstrate that this ELISA may be a suitable diagnostic tool for disease surveillance programmes and import/export veterinary certification of French cattle, goats and sheep.