ESCHERICHIA-COLI O157 - H7 AND ITS SIGNIFICANCE IN FOODS
ESCHERICHIA-COLI O157 - H7 AND ITS SIGNIFICANCE IN FOODS
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DOI：
10.1016/0168-1605(91)90143-d
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发表时间：
1991-04-01
影响因子：
5.4
通讯作者：
DOYLE, MP
中科院分区：
文献类型：
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作者：
DOYLE, MP
1982年，大肠杆菌O157:H7与两起与食物有关的不寻常胃肠道疾病暴发有关，最终被确定为一种病原体。这种微生物现在被认为是食源性疾病的一个重要原因，在美国、加拿大和英国都有暴发报告。疾病通常相当严重，可包括三种不同的综合征，即出血性结肠炎、溶血性尿毒症综合征和血栓性血小板减少性紫癜。大多数疫情与食用未煮熟的绞碎牛肉或较少饮用生牛奶有关。对零售生肉和家禽的调查显示，1.5%至3.5%的碎牛肉、猪肉、家禽和羊肉中含有大肠杆菌O157:H7。奶牛，特别是幼畜，已被确定为蓄水池。这种有机体是大多数大肠杆菌的典型，但确实具有显著的特征。例如，大肠杆菌O157:H7在24小时内不能发酵山梨醇，不具有β -葡萄糖醛酸酶活性，并且在44- 44.5℃下不能很好地生长或根本不能生长。这种生物没有异常的耐热性；将绞碎的牛肉加热到足以杀死典型的沙门氏菌菌株，也会杀死大肠杆菌O157:H7。致病性机制尚未完全阐明，但临床分离株产生一种或多种被认为是重要毒力因素的毒毒素。人们对食物中预先形成的维罗毒素的重要性知之甚少。在处理动物源性食品时采用适当的卫生做法，并在食用前对这类食品进行适当加热，是预防O157:H7大肠杆菌感染的重要控制措施。
Escherichia coli O157:H7 was conclusively identified as a pathogen in 1982 following its association with two food-related outbreaks of an unusual gastrointestinal illness. The organism is now recognized as an important cause of foodborne disease, with outbreaks reported in the U.S.A., Canada, and the United Kingdom. Illness is generally quite severe, and can include three different syndromes, i.e., hemorrhagic colitis, hemolytic uremic syndrome, and thrombotic thrombocytopenic purpura. Most outbreaks have been associated with eating undercooked ground beef or, less frequently, drinking raw milk. Surveys of retail raw meats and poultry revealed E. coli O157:H7 in 1.5 to 3.5% of ground beef, pork, poultry, and lamb. Dairy cattle, especially young animals, have been identified as a reservoir. The organism is typical of most E. coli, but does possess distinguishing characteristics. For example, E. coli O157:H7 does not ferment sorbitol within 24 h, does not possess beta-glucuronidase activity, and does not grow well or at all at 44-45.5-degrees-C. The organism has no unusual heat resistance; heating ground beef sufficiently to kill typical strains of salmonellae will also kill E. coli O157:H7. The mechanism of pathogenicity has not been fully elucidated, but clinical isolates produce one or more verotoxins which are believed to be important virulence factors. Little is known about the significance of pre-formed verotoxins in foods. The use of proper hygienic practices in handling foods of animal origin and proper heating of such foods before consumption are important control measures for the prevention of E. coli O157:H7 infections.