Background

We studied geographic distribution of diarrhoeagenic Escherichia coli virulence genes (DEC VGs) acquisition in travellers and investigated if they acquired highly virulent EAEC/STEC hybrid strains.

Methods

From the prospective, multicentre COMBAT study among 2001 Dutch travellers, 491 travellers were selected based on travel destination to 7 subregions. Faecal samples taken directly before and after travel were screened for nine DEC VGs with real-time PCR. Incidence proportions and rates were calculated for each gene and subregion.

Results

479 travellers were analysed. 21.8% acquired aggR (EAEC), with highest acquisition rates in Northern and Western Africa and 15.3% acquired eae (STEC/EPEC) with highest rates in travellers to Western and Eastern Africa. ETEC (elt or est gene) was acquired by 4.2% of travellers and acquisition of est was associated with traveller's diarrhoea. Overall, the risk of acquiring DEC VGs was low in Southern Africa and South America. Although the combination of aggR (EAEC) and stx1/2 (STEC) was acquired by 3 travellers, these genes could not be detected together in a single E. coli strain.

Conclusions

The risk of acquisition of DEC VGs strongly depends on the travel destination, with those travelling to Africa - except Southern Africa - having a higher risk.

中文翻译：

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洲际旅行者中获得人类腹泻性大肠杆菌毒力基因的风险：一项前瞻性，多中心研究。

背景

我们研究了旅行者中产生腹泻的大肠杆菌毒力基因（DEC VGs）的地理分布，并研究了他们是否获得了高毒力的EAEC / STEC杂种菌株。

方法

通过对2001年荷兰旅客进行的多中心COMBAT的前瞻性研究，根据前往7个子地区的目的地选择了491位旅客。在旅行前后直接采集的粪便样本通过实时PCR筛选了9种DEC VG。计算每个基因和亚区域的发病率和发生率。

结果

分析了479位旅客。购得aggR（EAEC）的比例为21.8％，在北非和西非的购置率最高，而购置eae（STEC / EPEC）的15.3％的购置西非和东非的旅行者比例最高。ETEC（elt或est基因）被4.2％的旅行者获取，est的获取与旅行者的腹泻有关。总体而言，在南部非洲和南美，获得DEC VG的风险较低。虽然组合AGGR（EAEC）和STX 1/2（STEC）通过3名旅行者获得的，这些基因不能在单个检测大肠杆菌菌株。

结论

购买DEC VG的风险在很大程度上取决于旅行目的地，前往非洲（南部非洲除外）的人的风险更高。