Muvhali Munyadziwa, Smith Anthony Marius, Rakgantso Andronica Moipone, Keddy Karen Helena
Centre for Enteric Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa.
Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
BMC Infect Dis. 2017 Oct 2;17(1):661. doi: 10.1186/s12879-017-2751-8.
Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) has become a significant pathogen in South Africa, and the need for improved molecular surveillance of this pathogen has become important. Over the years, multi-locus variable-number tandem-repeats analysis (MLVA) has become a valuable molecular subtyping technique for Salmonella, particularly for highly homogenic serotypes such as Salmonella Enteritidis. This study describes the use of MLVA in the molecular epidemiological investigation of outbreak isolates in South Africa.
Between the years 2013 and 2015, the Centre for Enteric Diseases (CED) received 39 Salmonella Enteritidis isolates from seven foodborne illness outbreaks, which occurred in six provinces. MLVA was performed on all isolates.
Three MLVA profiles (MLVA profiles 21, 22 and 28) were identified among the 39 isolates. MLVA profile 28 accounted for 77% (30/39) of the isolates. Isolates from a single outbreak were grouped into a single MLVA profile. A minimum spanning tree (MST) created from the MLVA data showed a close relationship between MLVA profiles 21, 22 and 28, with a single VNTR locus difference between them.
MLVA has proven to be a reliable method for the molecular epidemiological investigation of Salmonella Enteritidis outbreaks in South Africa. These foodborne outbreaks emphasize the importance of the One Health approach as an essential component for combating the spread of zoonotic pathogens such as Salmonella Enteritidis.
肠炎沙门氏菌肠炎亚种（肠炎沙门氏菌）已成为南非的一种重要病原体，因此加强对该病原体的分子监测变得至关重要。多年来，多位点可变数目串联重复序列分析（MLVA）已成为沙门氏菌一种有价值的分子分型技术，特别是对于像肠炎沙门氏菌这样高度同源的血清型。本研究描述了MLVA在南非暴发菌株分子流行病学调查中的应用。
2013年至2015年间，肠道疾病中心（CED）从六个省份发生的七起食源性疾病暴发中收到了39株肠炎沙门氏菌分离株。对所有分离株进行了MLVA分析。
在39株分离株中鉴定出三种MLVA谱型（MLVA谱型21、22和28）。MLVA谱型28占分离株的77%（30/39）。来自单次暴发的分离株被归为单一的MLVA谱型。根据MLVA数据构建的最小生成树（MST）显示MLVA谱型21、22和28之间关系密切，它们之间只有一个可变数目串联重复序列（VNTR）位点差异。
MLVA已被证明是南非肠炎沙门氏菌暴发分子流行病学调查的可靠方法。这些食源性疾病暴发强调了“同一健康”方法作为对抗诸如肠炎沙门氏菌等人畜共患病原体传播的重要组成部分的重要性。
