Kuzmina Natalia A, Lemey Philippe, Kuzmin Ivan V, Mayes Bonny C, Ellison James A, Orciari Lillian A, Hightower Dillon, Taylor Steven T, Rupprecht Charles E
Rabies Program, Division of High Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
PLoS One. 2013 Dec 3;8(12):e82348. doi: 10.1371/journal.pone.0082348. eCollection 2013.
The south-central skunk rabies virus (SCSK) is the most broadly distributed terrestrial viral lineage in North America. Skunk rabies has not been efficiently targeted by oral vaccination campaigns and represents a natural system of pathogen invasion, yielding insights to rabies emergence. In the present study we reconstructed spatiotemporal spread of SCSK in the whole territory of its circulation using a combination of Bayesian methods. The analysis based on 241 glycoprotein gene sequences demonstrated that SCSK is much more divergent phylogenetically than was appreciated previously. According to our analyses the SCSK originated in the territory of Texas ~170 years ago, and spread geographically during the following decades. The wavefront velocity in the northward direction was significantly greater than in the eastward and westward directions. Rivers (except the Mississippi River and Rio Grande River) did not constitute significant barriers for epizootic spread, in contrast to deserts and mountains. The mean dispersal rate of skunk rabies was lower than that of the raccoon and fox rabies. Viral lineages circulate in their areas with limited evidence of geographic spread during decades. However, spatiotemporal reconstruction shows that after a long period of stability the dispersal rate and wavefront velocity of SCSK are increasing. Our results indicate that there is a need to develop control measures for SCSK, and suggest how such measure can be implemented most efficiently. Our approach can be extrapolated to other rabies reservoirs and used as a tool for investigation of epizootic patterns and planning interventions towards disease elimination.
中南部臭鼬狂犬病病毒（SCSK）是北美分布最广泛的陆生病毒谱系。口服疫苗接种运动尚未有效针对臭鼬狂犬病，它代表了病原体入侵的自然系统，为狂犬病的出现提供了见解。在本研究中，我们结合贝叶斯方法重建了SCSK在其整个传播区域的时空传播。基于241个糖蛋白基因序列的分析表明，SCSK在系统发育上的差异比之前认为的要大得多。根据我们的分析，SCSK大约在170年前起源于德克萨斯州境内，并在随后的几十年里在地理上扩散。向北的波前速度明显大于向东和向西的速度。与沙漠和山脉不同，河流（密西西比河和格兰德河除外）并未构成动物疫病传播的重大障碍。臭鼬狂犬病的平均传播速度低于浣熊和狐狸狂犬病。病毒谱系在其区域内传播，几十年来地理扩散的证据有限。然而，时空重建表明，经过长时间的稳定后，SCSK的传播速度和波前速度正在增加。我们的结果表明需要制定针对SCSK的控制措施，并建议如何最有效地实施这些措施。我们的方法可以推广到其他狂犬病宿主，并用作调查动物疫病模式和规划疾病消除干预措施的工具。
