Figure 1

ELISA assay 1 analysis of human sera. The results of the IgG antibodies against TrV structural proteins were analysed at an absorbance of 490 nm. The cut-off value was the mean of the optical density (OD) plus three times the standard deviation, so sera samples with OD/cut-off values greater than 1.1 were considered positive; sera samples with OD/cut-off values 0.9 < OD/cut-off < 1.1 were considered indeterminate, and sera samples with values of OD/cut-off < 0.9 were considered negative.