肠产毒性大肠埃希菌的特性包括（）
A.常引起婴幼儿和旅游者腹泻
B.可引起溶血性尿毒综合征
C.可以是轻度腹泻，也可呈严重的霍乱样腹泻
D.致病物质包括耐热肠毒素
E.致病物质包括不耐热肠毒素
参考答案：A, C, D, E
解析：肠产毒性大肠埃希菌是5岁以下婴幼儿和旅游者腹泻的重要病原菌，临床症状可从轻度腹泻至严重的霍乱样腹泻。致病物质主要是肠毒素（不耐热毒素LT、耐热毒素ST）和定植因子。
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