• Journal of fish pathology
• /
• v.31 no.2
• /
• pp.71-79
• /
• 2018

Wild walleye pollock were caught from Goseong, The East Sea of Korea and examined for the existence of several fish pathogenic viruses; viral hemorrhagic septicemia virus (VHSV), nervous necrosis virus (NNV) and marine birnavirus (MABV). We collected 1,253 wild walleye pollock in total during February 2015 and August 2018. 324 spleen sample sets and 259 brain sample sets were made, and examined for the existence of the viruses mentioned above by reverse transcriptase polymerase chain reaction (RT-PCR). None of the target viruses were detected by one-step PCR. When some of these samples were further examined by two-step PCR, 19.7% (36/183) of spleen sample sets were positive for VHSV, and 4.4% (8/183) of spleen sample sets and 1.2% (3/259) of brain sample sets were positive for NNV. The target sequences of these viruses were clustered with those previously reported in Korea (Genotype IVa of VHSV, RGNNV genotype of NNV) by phylogenetic analysis. The activity of these viruses are not clear because virus isolation was not attempted, but probably very low because all the positive samples were detected by two-step PCR.