WOAH Reference Laboratory for VHS, National Institute of Fisheries Science, Busan 46083, Korea.
EU Reference Laboratory for VHS, Section for Fish and Shellfish Diseases, National Institute for Aquatic Resources, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark.
Virus Res. 2023 Jul 15;332:199133. doi: 10.1016/j.virusres.2023.199133. Epub 2023 May 18.
In May 2015, a high mortality event in farmed rainbow trout occurred in Jeollabuk-do province in Korea. Histopathological analysis revealed necrosis in the kidney, liver, branchial arch, and gills of moribund fish, and infectious hematopoietic necrosis virus (IHNV) was detected in the lesions by immunohistochemistry. Cytopathic effects were observed in EPC, FHM, and RTG-2 cell lines after inoculation with kidney and spleen tissues and IHNV was detected by reverse transcription polymerase chain reaction (PCR). The amplified PCR product was sequenced, and phylogenetic analysis placed IHNV in the JRt Nagano group. Both in vivo and in vitro trials were performed to compare the virulence properties between RtWanju15 isolate, which causes 100% mortality in imported fry, and a previous isolate RtWanju09 of the JRt Shizuoka group isolated from eggs of healthy broodfish. In vivo challenge with high dose on specific pathogen free (SPF) rainbow trout fry performed in Denmark with isolates RtWanju09, RtWanju15 and DF04/99 isolates showed a survival rates of 60%, 37.5% and 52.5% (average), respectively without statistical difference. The replication efficiency of the two isolates in the in vitro challenge was similar.
2015 年 5 月，韩国全罗北道发生一起养殖虹鳟鱼高死亡率事件。组织病理学分析显示濒死鱼的肾脏、肝脏、鳃弓和鳃组织坏死，免疫组织化学检测到传染性造血器官坏死病毒（IHNV）。用肾脏和脾脏组织接种后，在 EPC、FHM 和 RTG-2 细胞系中观察到细胞病变效应，并通过反转录聚合酶链反应（PCR）检测到 IHNV。扩增的 PCR 产物进行测序，系统进化分析将 IHNV 归入 JRt Nagano 组。进行了体内和体外试验，以比较导致进口鱼苗 100%死亡率的 RtWanju15 分离株与先前从健康亲鱼卵中分离的 JRt Shizuoka 组 RtWanju09 分离株的毒力特性。在丹麦用 RtWanju09、RtWanju15 和 DF04/99 分离株对无特定病原体（SPF）虹鳟鱼苗进行高剂量体内攻毒，存活率分别为 60%、37.5%和 52.5%（平均），无统计学差异。两种分离株在体外攻毒中的复制效率相似。
