Wang Yan, Lu Liang, Lan Ruiting, Salazar Joelle K, Liu Jingli, Xu Jianguo, Ye Changyun
State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Chinese Center for Disease Control and Prevention, Beijing 102206, China.
School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
Emerg Microbes Infect. 2017 Jun 7;6(6):e44. doi: 10.1038/emi.2017.28.
Listeria is ubiquitous in a variety of environments and can be isolated from a wide range of animal hosts. Rodents are capable of carrying pathogenic bacteria in their intestines, such as Listeria, and can disseminate those pathogens into the natural environment and to where human activity occurs. In this study, we investigated the occurrence and antimicrobial susceptibility of Listeria spp. isolated from wild rodents found in natural environments in China. We collected 341 intestinal fecal samples of rodents from five different regions of China, all representing different rodent habitats. The antimicrobial susceptibility of the Listeria spp. isolates obtained were firstly assessed using the Kirby-Bauer disk diffusion method. Thirty-one samples were positive for Listeria spp., of which 11 were positive for Listeria monocytogenes and seven were positive for Listeria ivanovii. Other species identified include Listeria innocua, Listeria fleischmannii and Listeria floridensis. All Listeria spp. isolates were sensitive to the majority of the antimicrobials tested, but largely resistant to oxacillin (94.1%) and cefuroxime (70.6%). All L. monocytogenes isolates were further characterized by serotyping, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). L. monocytogenes strains were grouped into three serotypes, five sequence types and five pulsotypes (PTs) by serotyping, MLST and PFGE, respectively. Almost half of the isolates (five of 11) belonged to serotype 1/2b, ST87 and PT1. This study determined that Listeria is carried in the intestinal tracts of wild rodents from multiple regions at a low rate, filling an epidemiological data gap on Listeria in natural environments in China.
李斯特菌在各种环境中普遍存在，并且可以从多种动物宿主中分离出来。啮齿动物能够在其肠道中携带病原菌，如李斯特菌，并可将这些病原体传播到自然环境以及人类活动的场所。在本研究中，我们调查了从中国自然环境中发现的野生啮齿动物分离出的李斯特菌属的发生情况和抗菌药物敏感性。我们从中国五个不同地区收集了341份啮齿动物的肠道粪便样本，所有样本均代表不同的啮齿动物栖息地。首先使用 Kirby-Bauer 纸片扩散法评估所获得的李斯特菌属分离株的抗菌药物敏感性。31份样本李斯特菌属呈阳性，其中11份单核细胞增生李斯特菌呈阳性，7份伊氏李斯特菌呈阳性。鉴定出的其他菌种包括无害李斯特菌、弗氏李斯特菌和佛罗里达李斯特菌。所有李斯特菌属分离株对大多数测试抗菌药物敏感，但对苯唑西林（94.1%）和头孢呋辛（70.6%）大多耐药。所有单核细胞增生李斯特菌分离株进一步通过血清分型、多位点序列分型（MLST）和脉冲场凝胶电泳（PFGE）进行鉴定。单核细胞增生李斯特菌菌株分别通过血清分型、MLST 和 PFGE 分为三种血清型、五种序列型和五种脉冲型（PTs）。几乎一半的分离株（11份中的5份）属于血清型1/2b、ST87和PT1。本研究确定，中国多个地区的野生啮齿动物肠道中携带李斯特菌的比例较低，填补了中国自然环境中李斯特菌流行病学数据的空白。
