Haake Christine J E, Waltzek Thomas B, Eckstrand Chrissy D, Hickey Nora, Reno Joetta Lynn, Wolking Rebecca M, Sriwanayos Preeyanan, Lovy Jan, Renner Elizabeth, Taylor Kyle R, Oliveira Ryan
Washington Animal Disease Diagnostic Laboratory, College of Veterinary Medicine, Washington State University, 1940 Olympia Avenue, Pullman, WA 99164, USA.
Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, 1845 Ott Road, Pullman, WA 99164, USA.
Viruses. 2025 Jul 23;17(8):1031. doi: 10.3390/v17081031.
We performed a diagnostic disease investigation on a wild smallmouth bass () with skin ulcers that was collected from Lake Oahe, South Dakota, following reports from anglers of multiple fish with similar lesions. Gross and histologic lesions of ulcerative dermatitis, myositis, and lymphocytolysis within the spleen and kidneys were consistent with largemouth bass virus (LMBV) infection. LMBV was detected by conventional PCR in samples of a skin ulcer, and the complete genome sequence of the LMBV (99,184 bp) was determined from a virus isolate obtained from a homogenized skin sample. A maximum likelihood (ML) phylogenetic analysis based on the major capsid protein (MCP) gene alignment supported the LMBV isolate (LMBV-SD-2023) as a member of the species , branching within the subclade of LMBV isolates recovered from North American largemouth () and smallmouth bass. This is the first detection of LMBV in wild smallmouth bass from South Dakota. The ultrastructure of the LMBV isolate exhibited the expected icosahedral shape of virions budding from cellular membranes. Viral nucleic acid in infected cells was visualized via in situ hybridization (ISH) within dermal granulomas, localized predominantly at the margin of epithelioid macrophages and central necrosis. Further sampling is needed to determine the geographic distribution, affected populations, and evolutionary relationship between isolates of LMBV.
在收到钓鱼者关于多条鱼出现类似损伤的报告后，我们对一条从南达科他州奥阿希湖采集的患有皮肤溃疡的野生小嘴黑鲈（ ）进行了疾病诊断调查。溃疡性皮肤炎、肌炎以及脾脏和肾脏内淋巴细胞溶解的大体和组织学损伤与大口黑鲈病毒（LMBV）感染相符。通过常规PCR在皮肤溃疡样本中检测到了LMBV，并从一份匀浆皮肤样本获得的病毒分离株中确定了LMBV的完整基因组序列（99,184 bp）。基于主要衣壳蛋白（MCP）基因比对的最大似然（ML）系统发育分析支持LMBV分离株（LMBV-SD-2023）属于该物种，在从北美大口黑鲈（ ）和小嘴黑鲈中分离出的LMBV分离株亚分支内分支。这是首次在南达科他州的野生小嘴黑鲈中检测到LMBV。LMBV分离株的超微结构显示出从细胞膜上芽生的病毒粒子预期的二十面体形状。通过原位杂交（ISH）在皮肤肉芽肿内观察到感染细胞中的病毒核酸，主要定位于上皮样巨噬细胞边缘和中央坏死区。需要进一步采样以确定LMBV分离株的地理分布、受影响种群以及进化关系。
