Laboratory for Foodborne Zoonoses, Public Health Agency of Canada, Lethbridge, Alberta, Canada.
J Clin Microbiol. 2012 Mar;50(3):788-97. doi: 10.1128/JCM.00669-11. Epub 2011 Dec 14.
Campylobacter spp. are a leading cause of bacterial gastroenteritis worldwide. The need for molecular subtyping methods with enhanced discrimination in the context of surveillance- and outbreak-based epidemiologic investigations of Campylobacter spp. is critical to our understanding of sources and routes of transmission and the development of mitigation strategies to reduce the incidence of campylobacteriosis. We describe the development and validation of a rapid and high-resolution comparative genomic fingerprinting (CGF) method for C. jejuni. A total of 412 isolates from agricultural, environmental, retail, and human clinical sources obtained from the Canadian national integrated enteric pathogen surveillance program (C-EnterNet) were analyzed using a 40-gene assay (CGF40) and multilocus sequence typing (MLST). The significantly higher Simpson's index of diversity (ID) obtained with CGF40 (ID = 0.994) suggests that it has a higher discriminatory power than MLST at both the level of clonal complex (ID = 0.873) and sequence type (ID = 0.935). High Wallace coefficients obtained when CGF40 was used as the primary typing method suggest that CGF and MLST are highly concordant, and we show that isolates with identical MLST profiles are comprised of isolates with distinct but highly similar CGF profiles. The high concordance with MLST coupled with the ability to discriminate between closely related isolates suggests that CFG40 is useful in differentiating highly prevalent sequence types, such as ST21 and ST45. CGF40 is a high-resolution comparative genomics-based method for C. jejuni subtyping with high discriminatory power that is also rapid, low cost, and easily deployable for routine epidemiologic surveillance and outbreak investigations.
空肠弯曲菌是全球细菌性肠胃炎的主要病因之一。在对空肠弯曲菌进行基于监测和暴发的流行病学调查时，分子亚型分析方法的区分能力需要得到增强，这对于我们了解其传播源和传播途径以及制定减少弯曲菌病发病率的缓解策略至关重要。我们描述了一种快速且高分辨率的空肠弯曲菌比较基因组指纹图谱（CGF）分析方法的开发和验证。使用 40 个基因检测（CGF40）和多位点序列分型（MLST）对来自加拿大国家综合肠道病原体监测计划（C-EnterNet）的农业、环境、零售和人类临床来源的 412 株分离株进行了分析。CGF40 获得的 Simpson 多样性指数（ID）显著较高（ID=0.994），表明其在克隆复合体水平（ID=0.873）和序列型水平（ID=0.935）的区分能力均高于 MLST。当 CGF40 用作主要分型方法时，获得的高 Wallace 系数表明 CGF 和 MLST 高度一致，并且我们表明具有相同 MLST 图谱的分离株包含具有不同但高度相似的 CGF 图谱的分离株。与 MLST 的高度一致性加上区分密切相关分离株的能力表明，CGF40 可用于区分高度流行的序列型，如 ST21 和 ST45。CGF40 是一种基于高分辨率比较基因组学的空肠弯曲菌亚型分析方法，具有高区分能力，同时还具有快速、低成本和易于常规流行病学监测和暴发调查部署的特点。
