Escherichia coli O157 感染及其致病分子機轉

Infection with Escherichia coli O157 and Its Molecular Mechanisms

大腸桿菌Escherichia coli 0157在世界各地導致人類嚴重的疾病。E. coli 0157對於生長的環境與溫度範圍很廣，以牛隻為帶菌者。最常見的傳染途徑是 食用受汙染的肉製品，或其他受牛隻產生的廢水而汙染的食物導致感染。E. coli 0157內含志賀毒素(Shiga toxin, Stx)，此毒素為一種效強力大的細胞毒素，也是造成出血性大腸炎(hemorrhagic colitis, HC)與溶血尿毒徵候群(hemolytic uremic syndrome, HUS)的主因。目前治療E. coli 0157：H7感染只能使用支持療法。本篇文章介紹E. coli 0157：H7的來源、傳染途徑與毒力因子及與2011年歐洲爆發E. coli 0104：H4之比較。因為此感染症藉由糞－口傳染的途徑很多，所以我們藉由一些方法阻隔傳染途徑，如牛奶要先消毒、水經氯氣處理、吃煮熟的食物與常洗手，即可避免感染。

Escherichia coli O157 is a pathogen that causes severe disease in humans worldwide. The organism adapts to a wide variety of conditions. Healthy cattle serve as a reservoir for E. coli O157, and bovine food products, produce, and dairy products contaminated with bovine waste are the most common sources for disease outbreaks. Shiga toxin, a potent cytotoxin, is the major virulence factor linked with the presentation of both hemorrhagic colitis and hemolytic uremic syndrome. Currently, the treatment of E. coli O157:H7 infections is limited to supportive care. This article describes the source, transmission, and virulence factors of E. coli O157:H7. We also compare it with E. coli O104:H4 from the 2011 European outbreak. Because fecal-to-oral transmission occurs by many routes, there is a need for barriers, such as milk pasteurization, water chlorination, cooking food, and hand washing, to prevent infection.