海南1例感染类鼻疽伯克霍尔德菌的溯源调查

目的 对海南1例类鼻疽患者进行感染溯源调查,为类鼻疽防控提供科学依据。方法 采集患者住所周边环境中的泥土、水等样品并进行类鼻疽病原菌分离。通过细菌学试验、16S rDNA测序、特异诊断PCR等方法对疑似菌株进一步鉴定。通过脉冲场凝胶电泳(PFGE)、多位点序列分型(MLST)、多位点可变数串联重复序列分析(MLVA_4)等技术比较并确定环境分离菌株与临床菌株的同源性。结果 采集的58份环境样品中,自患者及邻居家水井水中共分离出3株类鼻疽伯克霍尔德菌(简称类鼻疽伯克菌)。PFGE、MLST、MLVA等分子分型结果证实,1株自患者家井水中分离的类鼻疽伯克菌与患者临床分离株同源。结论 患者及其邻居家水井均被类鼻疽伯克菌污染,水井水很可能是该患者感染类鼻疽病的感染源。

Molecular tracing investigation for one case of melioidosis in Hainan Island,China

We aimed to identify the infectious source of a case of melioidosis and to provide evidence for the prevention and control of melioidosis in Hainan Province, China. Environmental sampling was carried out in the surrounding areas of the patient’s residence to perform the culture-based etiological survey. Suspected strains of Burkholderia pseudomallei were isolated using Ashdown selective plates and further confirmed by bacteriological tests, 16S rDNA sequencing, and specific diagnostic PCR assays. Environmental and clinical isolates of B. pseudomallei were characterized by pulsed field gel electrophoresis (PFGE), multi-locus sequence typing (MLST) and multi-locus variable tandem repeat analysis (MLVA), and then the homology and the genetic relationships between them were analyzed. Results showed that a total of 58 soil or water samples were collected in this study. Three strains of B. pseudomallei were isolated in three specimens of domestic well water, among which 2 from the patient’s house and 1 from the neighbor’s house respectively. One of these environmental isolates was identical to the clinical isolate of the patient by MLST, PFGE, and MLVA, indicating well water being the source of infection for this case of melioidosis. Domestic well waters at the melioidosis patient’s residence and the neighbor’s residence had been contaminated by B. pseudomallei, and it is probable that well water be the source of infection for this patient.