University of Florida, 2187 Mowry Road, 32611, Gainesville, Florida, USA.
Department of Fisheries & Oceans Canada, 501 University Crescent, Winnipeg, Manitoba, Canada.
Virus Res. 2019 Nov;273:197742. doi: 10.1016/j.virusres.2019.197742. Epub 2019 Sep 6.
An adult male harbour porpoise (Phocoena phocoena) stranded off the coast of Alaska displaying poor body condition, scattered mild ulcerative dermatitis, and necrotizing balanoposthitis. Necropsy findings included severe verminous panniculitis, pneumonia, hepatitis, and enteritis. Histopathological examination of skin lesions revealed a pustular epidermitis and dermatitis, with ballooning degeneration of keratinocytes and occasional amphophilic intracytoplasmic inclusion bodies. A swab sample collected from the ulcerative penile lesions was processed for virus isolation resulting in cytopathic effects observed in primary beluga whale kidney (BWK) cells. Transmission electron microscopy revealed bullet-shaped virions budding from the cell surface of infected BWK cells consistent with a rhabdovirus. A cDNA library was prepared using RNA extracted from infected cell culture supernatant and sequenced on an Illumina MiSeq sequencer. The near-complete genome of a novel rhabdovirus was recovered. Genetic and phylogenetic analyses based on the complete L gene supported the harbour porpoise rhabdovirus (HPRV) as a new species. HPRV clustered phylogenetically with dolphin rhabdovirus (DRV) and this cetacean rhabdovirus clade was found to be the sister group to members of the genus Perhabdovirus that infect fish. A specific nested RT-PCR assay detected HPRV RNA in the epaxial musculature of the harbour porpoise. Our results are consistent with a previous hypothesis that cetacean rhabdoviruses may have arisen following a host jump from fish and suggest that DRV and HPRV represent separate species belonging in a new genus within the family Rhabdoviridae. Further research is needed to determine the health impact of HPRV in harbour porpoise populations, its prevalence, and route of transmission.
一只在阿拉斯加沿海搁浅的成年雄性港湾鼠海豚，身体状况不佳，散布着轻度溃疡性皮炎和坏死性阴茎龟头炎。尸检结果包括严重的寄生虫性脂膜炎、肺炎、肝炎和肠炎。皮肤病变的组织病理学检查显示出脓疱性表皮炎和皮炎，角朊细胞气球样变性，偶尔有嗜碱性细胞内包涵体。从溃疡性阴茎病变处采集的拭子样本进行病毒分离，导致在原代白鲸肾（BWK）细胞中观察到细胞病变效应。透射电子显微镜显示，感染的 BWK 细胞表面有子弹形病毒粒子出芽，与弹状病毒一致。使用从感染细胞培养上清液中提取的 RNA 制备 cDNA 文库，并在 Illumina MiSeq 测序仪上进行测序。回收了一种新型弹状病毒的近全长基因组。基于完整 L 基因的遗传和系统发育分析支持港湾鼠海豚弹状病毒（HPRV）为一个新种。HPRV 在系统发育上与海豚弹状病毒（DRV）聚类，并且该鲸类弹状病毒进化枝被发现是感染鱼类的 Perhabdovirus 属成员的姊妹群。一种特异性巢式 RT-PCR 检测法在港湾鼠海豚的背肌中检测到了 HPRV RNA。我们的结果与先前的假设一致，即鲸类弹状病毒可能是从鱼类宿主跳跃而来的，这表明 DRV 和 HPRV 代表属于 Rhabdoviridae 科的新属中的两个不同种。需要进一步研究来确定 HPRV 对港湾鼠海豚种群的健康影响、其流行程度和传播途径。
