Figure 3: MIA fluorescence results, expressed as the ratio of the sample MFI over the positive control MFI X 100 (S/P ratio) on 20 ELISA positive (P), three doubtful (D), and five negative (N) horse samples from Austria, as determined with the ID Screen West Nile competition ELISA kit (ID Vet). The cut-off for the TBEV.EDIII antigen was determined to be 61.