Department of Brucellosis Research, Animal Health Research Institute, Agricultural Research Center, Giza, Egypt.
Department of Zoonoses, General Organization for Veterinary Services (GOVS), Giza, Egypt.
Transbound Emerg Dis. 2020 Nov;67(6):2435-2445. doi: 10.1111/tbed.13581. Epub 2020 May 1.
Brucella melitensis is a serious public health threat, with human infection exhibiting acute febrile illness and chronic health problems. The present study investigated the genetic diversity and epidemiological links of the important zoonotic bacterium B. melitensis in Egypt using multilocus variable-number tandem repeat analysis (MLVA-16) including eight minisatellite (panel 1) and eight microsatellite (panel 2, subdivided into 2A and 2B) markers. A total of 118 isolates were identified as B. melitensis biovar 3 by classical biotyping and Bruce-ladder assay. Although B. melitensis is primarily associated with infection in sheep and goats, most of B. melitensis isolates in this study were obtained from secondary hosts (cattle, buffaloes, humans and a camel) suggesting cross-species adaptation of B. melitensis to large ruminants in Egypt. The MLVA-16 scheme competently discriminated 70 genotypes, with 51 genotypes represented by single isolates, and the remaining 19 genotypes were shared among 67 isolates, suggesting both sporadic and epidemiologically related characteristics of B. melitensis infection. Matching of local genotypes with representatives of global genotypes revealed that the majority of Egyptian isolates analysed had a West Mediterranean descendance. As this study represents the first comprehensive genotyping and genetic analysis of B. melitensis from different sources in Egypt, the information generated from this study will augment knowledge about the main epidemiological links associated with this bacterium and will allow a better understanding of the current epidemiological situation of brucellosis in Egypt. Ultimately, this will help to adopt effective brucellosis intervention strategies in Egypt and other developing nations.
马耳他布鲁氏菌是一种严重的公共卫生威胁，人类感染该病后会出现急性发热疾病和慢性健康问题。本研究采用多位点可变数目串联重复分析（MLVA-16），包括 8 个微卫星（panel 1）和 8 个小卫星（panel 2，分为 2A 和 2B）标记物，对埃及重要的人畜共患病病原体马耳他布鲁氏菌的遗传多样性和流行病学联系进行了研究。总共 118 株分离株经经典生物分型和 Bruce-ladder 试验鉴定为马耳他布鲁氏菌 3 生物型。虽然马耳他布鲁氏菌主要与绵羊和山羊感染有关，但本研究中大多数马耳他布鲁氏菌分离株来自次级宿主（牛、水牛、人类和骆驼），这表明马耳他布鲁氏菌在埃及已适应大型反刍动物。MLVA-16 方案能够区分 70 种基因型，其中 51 种基因型由单个分离株代表，其余 19 种基因型由 67 个分离株共享，表明马耳他布鲁氏菌感染具有散发性和流行病学相关的特征。将本地基因型与全球基因型的代表相匹配表明，分析的大多数埃及分离株具有西地中海血统。由于本研究代表了对埃及不同来源的马耳他布鲁氏菌进行的首次全面基因分型和遗传分析，因此所产生的信息将增加有关与该细菌相关的主要流行病学联系的知识，并有助于更好地了解埃及布鲁氏菌病的当前流行病学情况。最终，这将有助于在埃及和其他发展中国家采取有效的布鲁氏菌病干预策略。
