MLVA distribution characteristics of Yersinia pestisin China and the correlation analysis

Abstract

BackgroundYersinia pestis, the aetiological agent of plague, has been well defined genotypically on local and worldwide scales. In November 2005, five cases of severe pneumonia of unknown causes, resulting in two deaths, were reported in Yulong, Yunnan province. In this study, we compared Y. pestis isolated from the Yulong focus to strains from other areas.ResultsTwo hundred and thirteen Y. pestis strains collected from different plague foci in China and a live attenuated vaccine strain of Y. pestis (EV76) were genotyped using multiple-locus variable-number tandem repeat analysis (MLVA) on 14 loci. A total of 214 Y. pestis strains were divided into 85 MLVA types, and Nei's genetic diversity indices of the various loci ranged between 0.02 - 0.76. Minimum spanning tree analysis showed that Y. pestis in China could be divided into six complexes. It was observed that Microtus strains were different from the other three biovar strains. Each plague focus had its own unique MLVA types.ConclusionThe strains isolated from Yulong, Yunnan province had a unique MLVA type, indicating a new clone group. Our results suggest that Yulong strains may have a close relationship with strains from the Qinghai-Tibet Plateau plague focus.

Single-Nucleotide Polymorphisms Reveal Spatial Diversity Among Clones ofYersinia pestisDuring Plague Outbreaks in Colorado and the Western United States

“…Our recent understanding of Y. pestis genetic diversity, evolution, and transmission patterns on several geographic scales has increased dramatically and suggests that plague exists as a clonal pathogen (Klevytska et al 2001, Achtman et al 2004, Girard et al 2004, Lowell et al 2005, Auerbach et al 2007, Touchman et al 2007, Vogler et al 2007, Zhang et al 2009, Morelli et al 2010, Cui et al 2013.…”

Whole genome multilocus sequence typing as an epidemiologic tool for Yersinia pestis

“…Based on the perfect matches observed for other linked isolates and the differences among group 2 strains resulting from SNPs, opposed to more rapidly changing VNTRs, we hypothesize that multiple strains were circulating in the area at the time of the patient’s exposure. Indeed, Santa Fe County, New Mexico, has been shown to produce multiple Y. pestis genotypes in a single year (Gibbons et al, 2012), a phenomenon that has also been noted in both China and Madagascar (Riehm et al, 2015; Zhang et al, 2009). wgMLST of additional Y. pestis isolates derived from fleas collected in the patient’s yard will be important for determining if an exact match to the patient isolate can be identified.…”

Yersinia pestis: examining wildlife plague surveillance in China and the USA

“…Yersinia pestis evolved in or near China and later spread to other parts of the world through multiple radiation events (Zhou et al 2004;Zhang et al 2009;Morelli et al 2010). The long-term association of Y. pestis in China has given rise to a diverse assemblage of plague transmission cycles and foci, a result of coupled evolution as the plague bacterium adapted to specific environmental factors, mammalian hosts and vector species.…”

“…Within China, there are at least 10 natural plague foci (Table 2), each associated with specific host and flea species (Dennis et al 1999). Recent genetic analy- (Ji et al 1983;Zhou et al 2004;Zhang et al 2009). Although there are multiple plague foci in China (Fig.…”