Sheep-associated malignant catarrhal fever (SA-MCF), the form of MCF that occurs in Brazil, is a severe, frequently fatal, infectious disease caused by ovine gammaherpesvirus-2 (OvHV-2), in which sheep are the asymptomatic hosts and cattle and other cloven-hoofed animals are the accidental hosts. This review provides a critical analysis of the historical, epidemiological aspects and the estimated economic impacts associated with SA-MCF in Brazil. Moreover, the clinical manifestations and pathological lesions associated with SA-MCF in cattle are reviewed and discussed and the phylogenetic distribution of OvHV-2 in Brazil is presented. OvHV-2 is the only MCF virus identified in animals from Brazil. It is recommended that a histopathologic diagnosis of SA-MCF be based on all aspects of vascular disease in the affected animal and not only lymphocytic/necrotizing vasculitis and/or fibrinoid change. Conformation of the intralesional participation of OvHV-2 in these alterations can be achieved by immunohistochemistry and/or in situ hybridization assays. Additionally, it is proposed that OvHV-2 should be considered as a possible infectious disease agent associated with the development of bovine respiratory disease in cattle. Furthermore, the possible role of the small intestine in the dissemination of OvHV-2 is discussed.

中文翻译：

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巴西恶性卡他热的流行病学、临床和病理学方面的综述

绵羊相关恶性卡他热 (SA-MCF) 是发生在巴西的 MCF 的一种形式，是一种由绵羊伽玛疱疹病毒 2 (OvHV-2) 引起的严重、经常致命的传染病，其中绵羊是无症状宿主，牛和其他偶蹄动物是偶然的宿主。本综述对巴西的 SA-MCF 相关的历史、流行病学方面和估计的经济影响进行了批判性分析。此外，回顾和讨论了与牛中 SA-MCF 相关的临床表现和病理病变，并介绍了巴西 OvHV-2 的系统发育分布。OvHV-2 是唯一在巴西动物中发现的 MCF 病毒。建议 SA-MCF 的组织病理学诊断基于受累动物血管疾病的所有方面，而不仅仅是淋巴细胞/坏死性血管炎和/或纤维蛋白样改变。OvHV-2 在这些改变中的病灶内参与的构象可以通过免疫组织化学和/或原位杂交测定来实现。此外，建议应将 OvHV-2 视为与牛的牛呼吸道疾病发展相关的可能的传染病病原体。此外，还讨论了小肠在 OvHV-2 传播中的可能作用。建议应将 OvHV-2 视为与牛的牛呼吸道疾病发展相关的可能的传染病病原体。此外，还讨论了小肠在 OvHV-2 传播中的可能作用。建议应将 OvHV-2 视为与牛的牛呼吸道疾病发展相关的可能的传染病病原体。此外，还讨论了小肠在 OvHV-2 传播中的可能作用。