The membranes were immersed in a blocking solution (5%(w/v) skim milk, 2% (w/v) bovine serum albumin (BSA) in PBST(PBS containing 0.05% Tween-20) overnight at 4◦C with continuousshaking, and then incubated with either S. mekongi-infected mouseserum (diluted at 1:1000) as the primary antibody or non-infectedmouse serum as the negative control for 2 h at room tempera-ture.