Department of Medicine, University of Cambridge, CB2 0QQ, UK.
Wellcome Trust Sanger Institute, Cambridge CB10 1SA, UK.
Nat Microbiol. 2017 Jan 23;2:16263. doi: 10.1038/nmicrobiol.2016.263.
The environmental bacterium Burkholderia pseudomallei causes an estimated 165,000 cases of human melioidosis per year worldwide and is also classified as a biothreat agent. We used whole genome sequences of 469 B. pseudomallei isolates from 30 countries collected over 79 years to explore its geographic transmission. Our data point to Australia as an early reservoir, with transmission to Southeast Asia followed by onward transmission to South Asia and East Asia. Repeated reintroductions were observed within the Malay Peninsula and between countries bordered by the Mekong River. Our data support an African origin of the Central and South American isolates with introduction of B. pseudomallei into the Americas between 1650 and 1850, providing a temporal link with the slave trade. We also identified geographically distinct genes/variants in Australasian or Southeast Asian isolates alone, with virulence-associated genes being among those over-represented. This provides a potential explanation for clinical manifestations of melioidosis that are geographically restricted.
环境细菌伯克霍尔德氏菌每年在全球造成约 16.5 万例人类类鼻疽病，并且也被归类为生物威胁剂。我们使用了来自 30 个国家的 469 株伯克霍尔德氏菌分离株的全基因组序列，这些序列是在 79 年时间内收集的，用于探索其地理传播。我们的数据表明，澳大利亚是早期的储主，随后传播到东南亚，然后再传播到南亚和东亚。在马来半岛和湄公河沿岸国家之间也观察到了反复的重新引入。我们的数据支持中美洲和南美洲分离株的非洲起源，并且在 1650 年至 1850 年间将伯克霍尔德氏菌引入了美洲，这与奴隶贸易提供了时间上的联系。我们还单独在澳大拉西亚或东南亚的分离株中发现了具有地理差异的基因/变体，其中包括毒力相关基因。这为类鼻疽病的临床表现提供了一个潜在的解释，因为这种病的临床表现是具有地理限制的。
