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目的 了解江苏省不同地区大肠埃希菌O15 7∶H7宿主动物带菌情况及其毒力基因阳性率。方法 在不同流行强度的地区分别设立监测点 ,采集猪、鸡、羊、牛等家畜家禽粪便标本 ,用免疫磁珠法进行病原菌分离培养 ,并用多重引物聚合酶链反应进行毒力基因分析。结果 6个监测点共采集猪、鸡、羊、牛等家畜家禽粪便标本 176 7份 ,共检出大肠埃希菌O15 7∶H7170株 ,总带菌率为 9.6 2 %。其中 ,以牛、羊带菌率较高 ,分别为 19.0 5 %和 12 .0 1%。对 85株菌进行SLT1、SLT2、eaeA和hly 4种毒力基因的检测 ,5 6 .4 7%的菌株毒力基因阳性 ,且以同时带有SLT2、eaeA和hly 3种毒力基因最为常见 ,占带毒菌株的 79.17%。结论 宿主动物带菌率与当地疾病流行强度有关 ,即有确诊病人的地区宿主动物带菌率及菌株毒力基因阳性率最高 ,其次为仅有零星病例的地区 ,而无相关病例的地区最低。提示加强宿主动物大肠埃希菌O15 7∶H7监测 ,对疫情的分析和疫情预测具有重要意义
Objective To understand the host bacteria carrying Escherichia coli O15 7:H7 in different areas of Jiangsu Province and the positive rate of virulence genes. Methods Monitoring points were set up in areas with different epidemic intensities. Samples of domesticated pigs from pigs, chickens, sheep and cattle were collected, and pathogenic bacteria were isolated and cultured by immunomagnetic beads method. Virulence genes were analyzed by polymerase chain reaction with multiple primers. Results A total of 176 feces samples of livestock, poultry, chickens, sheep and cattle were collected from 6 monitoring sites. Escherichia coli O15 7: H7170 strains were detected with a total carrier rate of 9.62%. Among them, cattle, sheep with higher rates of bacteria were 19.0 5% and 12 .0 1%. The detection of four virulence genes of SLT1, SLT2, eaeA and hly against 85 strains of bacteria showed that 56.7% strains were positive for virulence genes and the most common virulence genes were SLT2, eaeA and hly , Accounting for 79.17% of the strains of toxins. Conclusion The prevalence rate of host animals is related to the prevalence of endemic diseases. In other words, the prevalence of host strains and strains of virulence genes in the confirmed cases is the highest, followed by those with only sporadic cases and the lowest in the regions without related cases. Prompted to strengthen the host animal Escherichia coli O15 7:H7 monitoring, epidemic situation analysis and epidemic situation is of great significance