Wasteson Y, Johannessen G S, Bruheim T, Urdahl A M, O'Sullivan K, Rørvik L M
Norwegian School of Veterinary Science, Oslo, Norway.
Lett Appl Microbiol. 2005;40(5):373-7. doi: 10.1111/j.1472-765X.2005.01673.x.
To describe the distribution of Escherichia coli O157:H7 on a sporadically positive dairy farm and on possible contact farms over a one-year period.
Environmental and faecal samples from all animals at the farm, and faecal samples from animals at contact farms were analysed for E. coli O157:H7 by immunomagnetic separation methods or VIDAS. Confirmed isolates were tested for cytotoxicity in the Vero cell assay and typed by PFGE. Escherichia coli O157:H7 (stx2 and eae) of the same PFGE type were isolated from cattle, sheep, hens and environmental samples at variable levels during summer and fall 2002, but were not detected in 2003.
Escherichia coli O157:H7 had a widespread distribution on the farm investigated, but the original source of contamination could not be identified. The occurrence of this bacterium on the farm did not result in any detectable increase in gastrointestinal disease in the associated population.
Despite a low endemic level of E. coli O157:H7 in the Norwegian cattle population, the growth and spread of this potentially important bacterium may occur.
描述大肠杆菌O157:H7在一个偶尔呈阳性的奶牛场以及可能的接触农场中一年时间内的分布情况。
采用免疫磁珠分离法或VIDAS对该农场所有动物的环境样本和粪便样本，以及接触农场动物的粪便样本进行大肠杆菌O157:H7分析。对确认的分离株进行Vero细胞毒性试验，并通过脉冲场凝胶电泳（PFGE）分型。在2002年夏季和秋季，从牛、羊、母鸡及环境样本中不同程度地分离出相同PFGE型的大肠杆菌O157:H7（stx2和eae），但2003年未检测到。
在所调查的农场中，大肠杆菌O157:H7分布广泛，但污染的源头无法确定。该细菌在农场中的出现并未导致相关人群胃肠道疾病有任何可检测到的增加。
尽管挪威牛群中大肠杆菌O157:H7的地方流行水平较低，但这种潜在重要细菌仍可能生长和传播。
