目的　采用肠出血性大肠杆菌埃希氏菌 (EHEC)国际代表株O15 7∶H7-EDL933株 ,实验感染小鼠 (ICR) ,观察其感染和带菌消长情况。方法　ICR小鼠经口感染 ,剂量为 0 1～ 0 9ml(菌悬液浓度为 7 0× 10 8～ 4 0× 10 9CFU/ml) ,并在SPF动物实验室中饲养。结果　不同实验动物微生物等级的ICR小鼠对EDL933株表现出不同感染类型 ,Ⅰ级小鼠感染未成功 ;Ⅱ级小鼠为一过性排菌 (M =4h) ;Ⅲ级小鼠粪排菌中位数为 2 4h ,是Ⅱ级小鼠的 6倍。Ⅲ级小鼠发现盲肠带菌 ,阳性率为31 5 8% (6 / 19)。结论　研究结果提示 ,鼠可成为EHECO15 7∶H7的贮存宿主 ,可能是潜在的人类感染的传染源。不同实验动物微生物等级的ICR小鼠对EDL933株所表现出的感染类型 ,提示预防O15 7∶H7感染 ,可经口服菌苗来实现的可能性 Objective To infect ICR mice by using the representative strain of Enterotoxigenic Escherichia coli (EHEC) strain O15 7: H7-EDL933 to observe the infection and the growth of carriers. Methods ICR mice were orally infected with a dose of 0 1 ~ 0 9 ml (the bacterial suspension concentration was 70 × 10 8 ~ 4 0 × 10 9 CFU / ml) and were housed in the SPF animal laboratory. Results ICR mice of different experimental animals showed different infection types on EDL933 strain, the infection of grade Ⅰ mice was unsuccessful. The grade Ⅱ mice were transiently discharged (M = 4h) The median was 24 h, which was 6 times higher than in grade II mice. Grade Ⅲ mice were found to have cecal colonization with a positive rate of 31 58% (6/19). Conclusions The results suggest that the rat can be a storage host for EHECO15 7:H7 and may be a source of potential human infection. The type of infection exhibited by EDL933 strains in ICR mice of different experimental animal microbiological grades suggests the possibility of being achieved by oral vaccination against O15 7:H7 infection