Detection Of Virulence And Drug Resistance Of Escherichia Coli Pneumoniae Isolated From Fox In Qinhuangdao Area

In order to study the prevalence of fox pneumonia caused by E.coli,and the drug resistance trend of E.coli in Qinhuangdao,Hebei Province,the laboratory used routine methods to isolate bacteria and detect serotypes,virulence genes,drug resistance and drug resistance genes in this area by slide agglutination,PCR and drug susceptibility test,to provide data support for the prevalence of E.coli pneumonia and clinical treatment of pathogenic bacteria in the region.The research content and results are as follows:1.Pathological materia and bacterial identification:There were 450 clinical samples collected in total of lung,liver and nasal swabs of foxes who were diseased and dead from farms in Qinhuangdao area of Hebei Province.105 strains of E.coli pneumoniae were identified through differential culture,16SrRNA sequence analysis and biochemical identification,and 77 of them were pathogenic.2.Virulence gene test:The virulence genes were detected for the isolates,and 19virulence gene primers were used for PCR.The results showed that 77 strains of pathogenic E.coli carried 14 different virulence genes,and the detection rate of irp2was as high to 98.7%.The detection rates of fyuA,papC,fimC,iucD^a,and colv were also very high,between 50.6%and 85.7%,and the others carrying the lower ones were between 1.3%?5.2%.Others were not detected.9 serotypes were detected.O₁,O₈,O₇₈and O₁₂ were the dominant serotypes in this area.3.Drug resistance test:The drug sensitivity test was carried out on the isolates by K-B susceptibility paper method.There are 23 kinds of antibiotics were used,result showed that all 77 strains of isolates were drug resistance.Among them,all strains were resistant to sulfamethoxazole,and the resistance rate to penicillin,ampicillin,oxytetracycline,cefradine and other 9 drugs were very high,and both were more than95%,the resistance rate to doxycycline,florfenicol,streptomycin was between72%-88%,and to enrofloxacin,amikacin,ciprofloxacin and other 7 drugs were between42%-70%,and the lowest resistance rate was also above 30%.All strains were cross-resistance.Among the 23 drugs,the drug resistance spectrum was up to 23,and cross-resistance was serious.4.Detection of drug resistance genes:The resistance genes of 77 strains of drug-resistant isolates were detected by PCR.The results showed that 18 kinds of resistance genes were detected in 77 strains of drug-resistant strains,The results showed that the isolates mainly carried several resistance genes,such as parE,parC,gyrB and gyrA,which accounted for more than 92%of the fluoroquinolone-resistant strains,followed by oqxA and oqxB genes,which accounted for 62.3%and 66%of the fluoroquinolone-resistant strains,respectively.A few strains carried 7.5%of the qepA gene and 1.9%of qnrS gene.Some strains carried multiple types of resistance genes at the same time.Escherichia coli drug resistance gene carriers are very serious in this area.