Primers 24F1/24R1 and 24F2/24R2 corresponded to ORF24 of AbSV,whereas 25F1/25R1 and 25F2/25R2 corresponded to ORF25.24F1/24R1 and 25F1/25R1 were used to do the first round of nested PCR. 24F2/24R2 and 25F2/25R2 were used to do the second round of nested PCR. For primer details, please refer to