Epidemiology Study On Drug-resistant Of Escherichia Coli From Captive Wild Animals

Objective:To study and investigate the antibiotic resistant traits ofEscherichia coli isolated from animal, human and environment in Fuzhou animal zoo,which including the research on resistant phenotype and detection of integron I andinvestigation of the resistance gene of cephalosporings-resistant andquinolones-resistant Escherichia coli, so as to provide theoretical basis for knowing ofthe resistant states of Escherichia coli from animal zoo and for clinical rational usingof antibiotic in animal zoo.Methods:MAC and EMB were used to isolate and purify the Escherichia coli.The uidA gene was amplified by PCR to identify the Escherichia coli. Adherent genefimA and pathogenic gene of stxI, stxII,ST and LT were also detected. The brothmicro-dilution method recommended by Clinical and Laboratory standards Institute(CLSI) of American was used to detect the sensitivity of Escherichia coli strains toeight kinds of antibiotic. Meanwhile, intI1, parC and gyrA gene in Escherichia coliwere detected by PCR methods.Results:(1) Isolation rate of Escherichia coliThere were121strains of Escherichia coli isolated from all154samples. Theisolation rate of Escherichia coli from animals,human and environment was84.09%,79.55%and68.18%, respectively. The isolation rate from environment was lowerthan that from animal and human being source.(2) Detection of virulence-related genes in Escherichia coliThe isolation rate of fimA gene was70.2%in all121strains of Escherichia coliand which was68.91%、75%、66.67%in animal,human and environment, respectively.There was no stxI, stxII,ST and LT genes detected.(3) Antibiotic resistance of Escherichia coliAntibiotic sensitivity test revealed that the drug resistance rate of Escherichiacoli which isolated from animals to tetracycline was highest (63.51%), and followed by cefazolin (41.89%). The highest drug resistant rate of Escherichia coli fromphytophagous was appeared in sulfamethoxazole compound (56.52%), but sensitiveto gentamycin, ciprofloxacin and ampicillin. The resistance rates of Escherichia colistrains from carnivore, birds, omnivore and amphibian to tetracycline were45.45%,75%,75%and100%, respectively which were sensitive to sulfamethoxazolecompound and cefazolin.The antibiotic resistant rate of Escherichia coli from and water samples tosulfamethoxazole compound, tetracycline, ampicillin and cefazolin were93.33%,80%,80%and66.67%, respectively. The highest resistance rate in soil samplesappeared in sulfamethoxazole compound (90.91%), followed by tetracycline(72.73%), ampicillin (72.73%) and cefazolin(72.73%). The resistance rate ofEscherichia coli in water samples to sulfamethoxazole compound, ampicillin andtetracycline both were100%. The strains were sensitive to gentamycin, ciprofloxacinand cefotaxime.The antibiotic resistant rate of Escherichia coli from human being tosulfamethoxazole compound, tetracycline, ampicillin and cefazolin was87.5%,62.5%,59.38%,56.25%, respectively, and the strains were sensitive to ciprofloxacin. Thestrains isolated from veterinary and zoo keepers have the highest antibiotic sensitivityrate to sulfamethoxazole compound (81.82%), and the strains were sensitive tocefotaxime. The antibiotic resistant rate from common people to sulfamethoxazolecompound was90.48%, followed by cefazolin (66.67%), tetracycline (57.14%) andampicillin (57.14%).(4) The multidrug resistance of Escherichia coliEscherichia coli from animal showed29kinds of antibiotic resistant spectralpattern, which were8and14kinds in environment and human being respectively. Inall Escherichia coli from animal,19strains were sensitive to all antibiotic, but therewere48strains (64.86%) showed resistance to at least3antibiotics(5) Correlation between resistant genes and resistanceIn all the121strains of Escherichia coli isolated from all kind of sources, thedetection rate of ampC gene and gyrA gene was85.95%and83.4%respectively, which was24.79%in the detection of intI1gene，and most of gene positive strainsshowed resistance to5-8kinds of antibiotics.Conclusion:(1) All the121strains of Escherichia coli showed the highest resistance rate toSMZco, followed by tetracycline, cefazolin, chloramphenicol and ampicillin, andwere sensitive to cefotaxime and gentamicin.(2) The existence of fimA gene indicated that the resistant Escherichia coli alsocarried F1fimbriae virulence factor which may increase pathogenic probability.(3) strains with ampC gene or gyrA gene have relatively high resistance to Betalactamantibiotic and Quinolone antibiotic, respectively, which showed the correlationbetween resistant phenotype and resistant genotype.(4) There was strong correlation between intI1genes and multiple-resistance ofEscherichia Coli.