ABSTRACT

Most Shiga toxin-producing E. coli (STEC) infections are sporadic. Routine enhanced surveillance questionnaires of confirmed STEC cases in England contained promising data to conduct a case-control study to identify non-food exposures linked to the risk of becoming infected with different STEC serotypes, including O157, O26 and all others; this study pulled eligible cases from the recorded enhanced surveillance data. Controls were recruited from the general population and answered a comparable postal questionnaire. Logistic regression was performed to identify risk factors associated with STEC infection for O157, O26 and other serotype cases. In adjusted models, travel outside of the U.K. and childcare occupations raised the risk of infection for all serotypes. Day trips within the UK, exposure to dogs and contact with soil were linked to lower infection risk. Resident region within England was often linked to decreased risk. Summer season was linked to O157 and O26, but not other STEC. Swimming in the sea was linked to increased risk of infection by O157, but not other types of STEC. Correlations between exposures and infection were similar when the analysis was repeated excluding participants with a history of foreign travel. As the first case-control study in England to include sporadic non-O157 STEC, the varying risk factors between O157 and non-O157 cases suggest there are potentially unique reservoirs for different serotypes.

摘要

大多数产志贺毒素大肠杆菌(STEC) 感染都是散发性的。对英国确诊的 STEC 病例进行的常规强化监测调查问卷包含有希望的数据，可用于进行病例对照研究，以确定与感染不同 STEC 血清型（包括 O157、O26 和所有其他血清型）风险相关的非食物暴露；这项研究从记录的强化监测数据中提取了符合条件的病例。对照组是从普通人群中招募的，并回答了类似的邮寄问卷。进行逻辑回归以确定与 O157、O26 和其他血清型病例 STEC 感染相关的危险因素。在调整后的模型中，英国境外旅行和儿童保育职业会增加所有血清型的感染风险。英国境内的一日游、接触狗和接触土壤与较低的感染风险有关。英格兰境内的居住地区通常与风险降低有关。夏季与 O157 和 O26 有关，但与其他 STEC 无关。在海里游泳与 O157 感染风险增加有关，但与其他类型的 STEC 无关。当排除有国外旅行史的参与者进行重复分析时，暴露与感染之间的相关性相似。作为英国第一项纳入散发性非 O157 STEC 的病例对照研究，O157 和非 O157 病例之间不同的危险因素表明，不同血清型可能存在独特的储存库。