The use of ELISA for the detection of African horse sickness viruses in Culicoides midges.

The use of ELISA for the detection of African horse sickness viruses (AHSV) in midges preserved in 5.0% formalin was evaluated. No differences were detected by ELISA when testing AHSV infected batches of Culicoides midges collected in diluent with or without the addition of formalin. The ELISA was considered highly sensitive and easily distinguished between non-infected midges and batches containing varying numbers of infected and non-infected midges. Positive ELISA reactions were detected with formalin-preserved midges collected from the south of Spain during the 1988 AHSV epizootic. The assay, therefore, may be used in surveillance studies of either fresh or formalin-preserved midges to identify undisclosed and persistent AHSV foci. This information would be useful in helping to eradicate the virus from Europe and North Africa.