Norwich Medical School, University of East Anglia, Norwich, UK.
NIHR Health Protection Research Unit in Gastrointestinal Infections, Liverpool, UK.
Lett Appl Microbiol. 2020 Aug;71(2):179-186. doi: 10.1111/lam.13303. Epub 2020 May 15.
Shiga toxin-producing Escherichia coli is carried in the intestine of ruminant animals, and outbreaks have occurred after contact with ruminant animals or their environment. The presence of STEC virulence genes in the environment was investigated along recreational walking paths in the North West and East Anglia regions of England. In all, 720 boot sock samples from walkers' shoes were collected between April 2013 and July 2014. Multiplex PCR was used to detect E. coli based on the amplification of the uidA gene and investigate STEC-associated virulence genes eaeA, stx1 and stx2. The eaeA virulence gene was detected in 45·5% of the samples, where stx1 and/or stx2 was detected in 12·4% of samples. There was a difference between the two regions sampled, with the North West exhibiting a higher proportion of positive boot socks for stx compared to East Anglia. In univariate analysis, ground conditions, river flow and temperature were associated with positive boot socks. The detection of stx genes in the soil samples suggests that STEC is present in the English countryside and individuals may be at risk for infection after outdoor activities even if there is no direct contact with animals. SIGNIFICANCE AND IMPACT OF THE STUDY: Several outbreaks within the UK have highlighted the danger of contracting Shiga toxin-producing Escherichia coli from contact with areas recently vacated by livestock. This is more likely to occur for STEC infections compared to other zoonotic bacteria given the low infectious dose required. While studies have determined the prevalence of STEC within farms and petting zoos, determining the risk to individuals enjoying recreational outdoor activities that occur near where livestock may be present is less researched. This study describes the prevalence with which stx genes, indicative of STEC bacteria, were found in the environment in the English countryside.
产志贺毒素大肠杆菌存在于反刍动物的肠道中，接触反刍动物或其环境后会爆发疫情。本研究沿英格兰西北部和东安格利亚地区的休闲步道，调查了环境中 STEC 毒力基因的存在情况。2013 年 4 月至 2014 年 7 月期间，共采集了 720 名步行者鞋上的靴袜样本。采用多重 PCR 法，基于 uidA 基因的扩增检测大肠杆菌，并调查与 STEC 相关的毒力基因 eaeA、stx1 和 stx2。45.5%的样本中检测到 eaeA 毒力基因，其中 12.4%的样本中检测到 stx1 和/或 stx2。两个采样区域存在差异，与东安格利亚相比，西北部靴袜样本 stx 阳性率更高。单因素分析显示，地面条件、河流水位和温度与靴袜阳性有关。土壤样本中 stx 基因的检测表明，STEC 存在于英国农村，即使没有与动物直接接触，个体在户外活动后也可能有感染的风险。研究的意义和影响：在英国发生的几起疫情表明，接触牲畜刚离开的区域有感染产志贺毒素大肠杆菌的危险。与其他人畜共患病细菌相比，由于所需的感染剂量较低，STEC 感染的风险更大。虽然已有研究确定了农场和宠物动物园中 STEC 的流行情况，但对在可能存在牲畜的地方附近享受休闲户外活动的个体所面临的风险的研究较少。本研究描述了在英国农村环境中 stx 基因（指示 STEC 细菌）的存在情况。
