1 PHE South East, Surrey and Sussex HPT, Parkside, Chart Way, Horsham RH12 1XA, UK.
2 Gastrointestinal Bacteria Reference Unit, Public Health England, 61 Colindale Avenue, London NW9 5HT, UK.
J Med Microbiol. 2019 Jun;68(6):930-939. doi: 10.1099/jmm.0.000970. Epub 2019 Apr 17.
This study describes the epidemiology of Shiga toxin-producing Escherichia coli (STEC) infections in a population in the South East of England.
From 1 November 2013 to 31 March 2017 participating diagnostic laboratories reported Shiga toxin gene (stx) positive real-time PCR results to local public health teams. Stx positive faecal samples/isolates were referred to the Gastrointestinal Bacteria Reference Unit (GBRU) for confirmation by culture and typing by whole genome sequencing (WGS). Key clinical information was collected by public health teams.Results/Key findings. Altogether, 548 faecal specimens (420 were non-travel associated) were stx positive locally, 535 were submitted to the GBRU. STEC were isolated from 42 %, confirmed by stx PCR in 21 % and 37 % were PCR negative. The most common non-travel associated STEC serogroups were O157, O26, O146 and O91. The annualized incidence of confirmed STEC infections (PCR or culture) was 5.8 per 100 000. The ratio of O157 to non-O157 STEC serogroups was 1:7. The annualized incidence of non-O157 haemolytic uraemic syndrome-associated Escherichia coli (HUSEC) strains was 0.4 per 100 000. Bloody diarrhoea was reported by 58 % of cases infected with E. coli O157, 33 % of cases infected with non-O157 HUSEC strains and 12 % of other lower risk non-O157 strains. Overall, 76 % of non-O157 HUSEC isolates possessed the eae virulence gene.
HUSEC including serogroup O157 were uncommon and more likely to cause bloody diarrhoea than other STEC. The routine use of stx PCR testing can influence clinical management. Understanding the local epidemiology facilitates a proportionate public health response to STEC, based on clinical and microbiological characteristics including stx subtype(s).
本研究描述了英格兰东南部人群中志贺毒素产生大肠杆菌（STEC）感染的流行病学情况。
2013 年 11 月 1 日至 2017 年 3 月 31 日，参与的诊断实验室向当地公共卫生团队报告实时聚合酶链反应（PCR）检测到志贺毒素基因（stx）阳性的结果。stx 阳性的粪便样本/分离物被送往胃肠道细菌参考单位（GBRU）进行培养确认，并通过全基因组测序（WGS）进行分型。公共卫生团队收集了关键的临床信息。结果/主要发现：共有 548 份粪便标本（420 份非旅行相关）在当地 stx 阳性，535 份标本提交给 GBRU。STEC 的分离率为 42%，stx-PCR 确认率为 21%，37%为 PCR 阴性。最常见的非旅行相关 STEC 血清群为 O157、O26、O146 和 O91。确诊 STEC 感染（PCR 或培养）的年发病率为每 10 万人 5.8 例。O157 与非-O157 STEC 血清群的比例为 1:7。非 O157 溶血性尿毒综合征相关大肠杆菌（HUSEC）菌株的年发病率为每 10 万人 0.4 例。58%感染 O157 大肠杆菌的病例报告有血性腹泻，33%感染非-O157 HUSEC 菌株的病例报告有血性腹泻，12%感染其他低风险非-O157 菌株的病例报告有血性腹泻。总体而言，76%的非-O157 HUSEC 分离株携带 eae 毒力基因。
HUSEC 包括 O157 血清群并不常见，比其他 STEC 更有可能引起血性腹泻。常规使用 stx-PCR 检测可影响临床管理。了解当地的流行病学情况有助于根据临床和微生物学特征（包括 stx 亚型）对 STEC 做出适当的公共卫生反应。
