Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany.
Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Südufer 10, 17493 Greifswald-Insel Riems, Germany.
Viruses. 2020 Feb 20;12(2):237. doi: 10.3390/v12020237.
Cowpox virus (CPXV) belongs to the genus in the family and is endemic in western Eurasia. Based on seroprevalence studies in different voles from continental Europe and UK, voles are suspected to be the major reservoir host. Recently, a CPXV was isolated from a bank vole () in Germany that showed a high genetic similarity to another isolate originating from a Cotton-top tamarin (). Here we characterize this first bank vole-derived CPXV isolate in comparison to the related tamarin-derived isolate. Both isolates grouped genetically within the provisionally called CPXV-like 3 clade. Previous phylogenetic analysis indicated that CPXV is polyphyletic and CPXV-like 3 clade represents probably a different species if categorized by the rules used for other orthopoxviruses. Experimental infection studies with bank voles, common voles () and Wistar rats showed very clear differences. The bank vole isolate was avirulent in both common voles and Wistar rats with seroconversion seen only in the rats. In contrast, inoculated bank voles exhibited viral shedding and seroconversion for both tested CPXV isolates. In addition, bank voles infected with the tamarin-derived isolate experienced a marked weight loss. Our findings allow for the conclusion that CPXV isolates might differ in their replication capacity in different vole species and rats depending on their original host. Moreover, the results indicate host-specific differences concerning CPXV-specific virulence. Further experiments are needed to identify individual virulence and host factors involved in the susceptibility and outcome of CPXV-infections in the different reservoir hosts.
牛痘病毒（CPXV）属于痘病毒科正痘病毒属，在欧亚西部流行。根据来自欧洲大陆和英国不同田鼠的血清流行率研究，田鼠可能是主要的储存宿主。最近，从德国的一种鼷鼠（）中分离到一种 CPXV，其与另一种源自棉顶狨猴（）的分离株具有很高的遗传相似性。在此，我们将这种来自鼷鼠的 CPXV 分离株与相关的狨猴分离株进行了特征描述。这两个分离株在遗传上均属于暂定称为 CPXV 样 3 分支的范围内。先前的系统发育分析表明，CPXV 是多源的，如果按照用于其他正痘病毒的规则进行分类，CPXV 样 3 分支可能代表不同的物种。用鼷鼠、普通田鼠（）和 Wistar 大鼠进行的实验感染研究显示出非常明显的差异。在普通田鼠和 Wistar 大鼠中，该鼷鼠分离株无毒性，仅在大鼠中观察到血清转化。相比之下，接种的鼷鼠对两种测试的 CPXV 分离株都显示出病毒脱落和血清转化。此外，感染了狨猴分离株的鼷鼠体重明显减轻。我们的研究结果表明，CPXV 分离株在不同田鼠物种和大鼠中的复制能力可能因它们的原始宿主而异。此外，结果表明 CPXV 特异性毒力存在宿主特异性差异。需要进一步的实验来鉴定参与 CPXV 感染不同储存宿主易感性和结果的个体毒力和宿主因素。
