Abstract

Brucellosis is a widely prevalent zoonotic disease of major public health significance. A collection of Brucella melitensis and Brucella abortus field isolates of animal and human origin were subjected to MLVA-15 typing followed by phylogeography studies. The MLVA-15 analysis of B. melitensis (n = 65) field isolates resulted in 48 different profiles. The panel I marker bruce45 was found to be most conserved, while the rest of the panel I markers showed low to moderate length polymorphism. Among the panel II markers, bruce04, bruce16 and bruce30 showed a high discriminatory index. The MLVA-15 typing of 13 B. abortus field isolates revealed 13 different genotypes with panel II markers showing higher discriminatory ability vis-à-vis panel I. The minimum spanning tree analysis (MST) in comparison with isolates from the international database revealed that all B. melitensis and B. abortus isolates from this study belonged to the ‘Eastern Mediterranean’ and the ‘abortus C’ lineage, respectively. The MLVA-15 typing could differentiate field isolates of B. abortus and B. melitensis originating from different regions, reaffirming the technique’s potential of high resolution and suitability for local epidemiological studies. The MLVA scheme also has the advantage of comparison of local isolates with a worldwide database, allowing for phylogeographical studies.

摘要

布鲁氏菌病是一种广泛流行的人畜共患疾病，具有重要的公共卫生意义。对动物和人类来源的羊种布鲁氏菌和流产布鲁氏菌野外分离株进行 MLVA-15 分型，然后进行系统发育地理学研究。B. melitensis ( n = 65) 野外分离株的 MLVA-15 分析 产生了 48 种不同的概况。小组 I 标记 bruce45 被发现是最保守的，而小组 I 标记的其余部分显示低到中等长度的多态性。在 panel II 标记中，bruce04、bruce16 和 bruce30 显示出高辨别指数。13流产芽孢杆菌的MLVA-15分型田间分离株揭示了 13 种不同的基因型，其中组 II 标记显示出比组 I 更高的辨别能力。与国际数据库中的分离株相比，最小生成树分析 (MST) 显示所有 B. melitensis 和B. abortus分离自这项研究分别属于“东地中海”和“流产 C”谱系。MLVA-15 分型可以区分B. abortus和B. melitensis的野外分离株源自不同地区，重申该技术的高分辨率潜力和适用于当地流行病学研究。MLVA 方案还具有将本地分离株与全球数据库进行比较的优势，从而可以进行系统地理学研究。