Cross‐species transmission and evolutionary dynamics of canine distemper virus during a spillover in African lions of Serengeti National Park
Cross‐species transmission and evolutionary dynamics of canine distemper virus during a spillover in African lions of Serengeti National Park
复制标题
塞伦盖蒂国家公园非洲狮溢出期间犬瘟热病毒的跨物种传播和进化动态
作者：
Julie K. Weckworth;Brian W. Davis;E. Dubovi;N. Fountain‐Jones;C. Packer;S. Cleaveland;M. Craft;E. Eblate;M. Schwartz;L. S. Mills;M. Roelke
病原体从宿主扩散到新宿主种群的结果可能是从在受体种群中没有进一步传播的“死胡同”，到流行病传播，甚至在新宿主中建立。了解在新宿主中导致离散结果的溢出事件的进化流行病学是预测风险的关键，并可导致更好地理解出现的机制。在这里，我们使用贝叶斯系统动力学方法研究了1993至1994年间塞伦盖蒂生态区非洲狮群(Panthera Leo)在犬瘟热病毒(CDV)溢出事件期间的跨物种传播和进化动力学，该事件导致临床疾病和种群下降。利用四个物种的21个接近完整的病毒基因组，我们发现这次大规模疫情很可能是在疾病检测和CDV在狮子中爆炸性传播的前一年由单一的跨物种溢出事件从犬科动物宿主到非犬科动物宿主引发的。其他非犬科物种的跨物种传播可能助长了CDV在空间结构的狮群中的高流行率。多条证据表明，斑点鬣狗(Crocuta Crocuta)可能是狮子接触CDV的最接近来源。我们报告了在犬和非犬中发现的分离CDV毒株的13个核苷酸替换。我们的结果与病毒进化在CDV在暴发期间溢出后在非犬类宿主中出现的假设一致，表明宿主对临床感染的屏障可以限制CDV在新宿主物种中溢出的结果。
The outcome of pathogen spillover from a reservoir to a novel host population can range from a “dead‐end” when there is no onward transmission in the recipient population, to epidemic spread and even establishment in new hosts. Understanding the evolutionary epidemiology of spillover events leading to discrete outcomes in novel hosts is key to predicting risk and can lead to a better understanding of the mechanisms of emergence. Here we use a Bayesian phylodynamic approach to examine cross‐species transmission and evolutionary dynamics during a canine distemper virus (CDV) spillover event causing clinical disease and population decline in an African lion population (Panthera leo) in the Serengeti Ecological Region between 1993 and 1994. Using 21 near‐complete viral genomes from four species we found that this large‐scale outbreak was likely ignited by a single cross‐species spillover event from a canid reservoir to noncanid hosts <1 year before disease detection and explosive spread of CDV in lions. Cross‐species transmission from other noncanid species probably fuelled the high prevalence of CDV across spatially structured lion prides. Multiple lines of evidence suggest that spotted hyenas (Crocuta crocuta) could have acted as the proximate source of CDV exposure in lions. We report 13 nucleotide substitutions segregating CDV strains found in canids and noncanids. Our results are consistent with the hypothesis that virus evolution played a role in CDV emergence in noncanid hosts following spillover during the outbreak, suggest that host barriers to clinical infection can limit outcomes of CDV spillover in novel host species.
影响因子：
3.3
作者：
Nikolin, Veljko M.;Wibbelt, Gudrun;East, Marion L.
通讯作者：
East, Marion L.