An outbreak of canine distemper virus in a private zoo in eastern Tennessee in July 2016 led to fatal clinical disease in 5 adult, wild-caught Linnaeus's 2-toed sloths (Choloepus didactylus). Clinical signs included hyporexia, lethargy, mucopurulent nasal discharge, and oral and facial ulcers. At necropsy, affected animals had crusts and ulcers on the lips, nose, tongue, and oral cavity. Microscopically, all sloths had widespread, random, hepatic necrosis; lymphoid depletion; and bronchointerstitial pneumonia. The central nervous system did not contain gross or histopathologic lesions in any of the 5 sloths, although immunoreactivity for viral antigen was present within vessel walls. Epithelial cells and histiocytes within numerous organs contained intranuclear and intracytoplasmic inclusions and occasional syncytial cells. Canine distemper virus was confirmed with immunohistochemistry and virus isolation. Viral sequencing identified the novel American-4 strain prevalent in eastern Tennessee wildlife. This is the first pathologic characterization of canine distemper virus infection in sloths (family Choloepodidae, order Pilosa) and emphasizes the significant morbidity and mortality in this species.

中文翻译：

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Linnaeus的2趾Sl（Choloepus didactylus）中的天然犬瘟热病毒感染。

2016年7月，田纳西州东部一家私人动物园爆发了犬瘟热病毒，导致5名成年野生野生Linnaeus的2趾树懒（Choloepus didactylus）导致致命的临床疾病。临床体征包括低氧，嗜睡，粘液性鼻分泌物以及口腔和面部溃疡。尸检时，患病动物的嘴唇，鼻子，舌头和口腔上有结rust和溃疡。在显微镜下，所有树懒都具有广泛的，随机的，肝坏死的现象。淋巴消耗 和支气管间质性肺炎。尽管在血管壁内存在病毒抗原的免疫反应性，但在5个树懒中的任何一个中，中枢神经系统都没有肉眼或组织病理学损伤。许多器官内的上皮细胞和组织细胞含有核内和胞浆内包涵体，偶有合胞细胞。通过免疫组织化学和病毒分离确认了犬瘟热病毒。病毒测序确定了在田纳西州东部野生动物中流行的新型American-4菌株。这是懒惰犬（犬科动物，Pilosa犬）犬瘟热病毒感染的第一个病理学特征，并强调了该物种的高发病率和死亡率。