Seroprevalence of bluetongue virus antibodies in sheep and goats in Kerala State, India

The results presented here record the first confirmation of bluetongue virus (BTV) antibody in sheep and goats in Kerala State. A total of 1,010 sera collected from the 14 districts within the state were screened for the presence of group-specific BTV antibodies by dot enzyme-linked immunosorbent assay (dot ELISA). Positive samples were obtained from 12 of the 14 districts. The overall BTV antibody prevalence was 5.1 +/- 1.9% (at 95% confidence level) although the prevalence levels were consistently higher in organised farms than in the field population. Comparative tests carried out using the dot ELISA and competitive ELISA (C ELISA) showed a good agreement for all the positive sera. The dot ELISA was simple to perform, economic and rapid, and is therefore ideally suited for routine screening for BTV antibody at the farm level.