Persistence of enterohemorrhagic Escherichia coli O157 :H7 in soil and on leaf lettuce and parsley grown in fields treated with contaminated manure composts or irrigation water
Persistence of enterohemorrhagic Escherichia coli O157 :H7 in soil and on leaf lettuce and parsley grown in fields treated with contaminated manure composts or irrigation water
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DOI：
10.4315/0362-028x-67.7.1365
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发表时间：
2004-07-01
影响因子：
2
通讯作者：
Jiang, XP
中科院分区：
文献类型：
--
作者：
Islam, M;Doyle, MP;Jiang, XP
近年来，与莴苣和其他叶类作物相关的肠出血性大肠杆菌O 157：H7感染的爆发越来越频繁。在许多疫情中，受污染的粪便和受污染的灌溉水可能是病原体的传播媒介。本研究对E.大肠杆菌O 157：H7的污染家禽或牛粪堆肥施肥或受污染的灌溉水处理的土壤和生菜和欧芹生长在这些土壤在自然环境条件下进行了测定。25个地块，每个1.8 4.6米，用于每种作物，有五个治疗（一个没有堆肥，三个与每三个堆肥，一个没有堆肥，但用受污染的水处理）和五个重复地块，每个治疗。用一株无毒的E. coli O157：H7。病原体浓度为107 CFU/g堆肥和10（5）CFU/ml水。2002年10月下旬，在生菜和欧芹幼苗移植的前一天，将受污染的堆肥以每公顷4.5公吨的量施于田间土壤中。在幼苗移植后3周，将污染的灌溉水仅施用于植物一次，作为每种作物5个小区的处理，每小区2升。E.大肠杆菌O 157：H7持续154至217天，在土壤中修订与污染堆肥和生菜和欧芹上检测到的77和177天后，幼苗种植。在E.大肠杆菌O 157：H7的持久性仅基于堆肥类型。E.大肠杆菌O 157：H7在欧芹覆盖的土壤中比在莴苣收获后裸露的莴苣地块土壤中存活时间更长（>60天）。在所有情况下，E.大肠杆菌O 157：H7在土壤中的持续时间大于5个月。
Outbreaks of enterohemorrhagic Escherichia coli O157:H7 infections associated with lettuce and other leaf crops have occurred with increasing frequency in recent years. Contaminated manure and polluted irrigation water are probable vehicles for the pathogen in many outbreaks. In this study, the occurrence and persistence of E. coli O157:H7 in soil fertilized with contaminated poultry or bovine manure composts or treated with contaminated irrigation water and on lettuce and parsley grown on these soils under natural environmental conditions was determined. Twenty-five plots, each 1.8 by 4.6 m, were used for each crop, with five treatments (one without compost, three with each of the three composts, and one without compost but treated with contaminated water) and five replication plots for each treatment. Three different types of compost, PM-5 (poultry manure compost), 338 (dairy manure compost), and NVIRO-4 (alkaline- stabilized dairy manure compost), and irrigation water were inoculated with an avirulent strain of E. coli O157:H7. Pathogen concentrations were 107 CFU/g of compost and 10(5) CFU/ml of water. Contaminated compost was applied to soil in the field as a strip at 4.5 metric tons per hectare on the day before lettuce and parsley seedlings were transplanted in late October 2002. Contaminated irrigation water was applied only once on the plants as a treatment in five plots for each crop at the rate of 2 liters per plot 3 weeks after the seedlings were transplanted. E. coli O157:H7 persisted for 154 to 217 days in soils amended with contaminated composts and was detected on lettuce and parsley for up to 77 and 177 days, respectively, after seedlings were planted. Very little difference was observed in E. coli O157:H7 persistence based on compost type alone. E. coli O157:H7 persisted longer (by >60 days) in soil covered with parsley plants than in soil from lettuce plots, which were bare after lettuce was harvested. In all cases, E. coli O157:H7 in soil, regardless of source or crop type, persisted for >5 months after application of contaminated compost or irrigation water.