Antibiotic resistance characteristics of Escherichia coli strains carrying and not carrying virulence genes isolated from healthy people in Nguyen Xa commune, Vu Thu district, Thai Binh province

Abstract

The study used 169 E. coli strains isolated from fecal samples of healthy people in Nguyen Xa commune, Vu Thu district, Thai Binh province in 2016 to evaluate the antibiotic resistance characteristics of E. coli strains carrying and non-carrying virulent genes. The presence of virulence genes in E. coli was determined by the multiplex PCR method and antibiotic profile of the bacteria was determined by disk diffusion method according to CLSI guidelines. The results
showed that the rate of E. coli strains carrying virulence genes was 41.1%, of which the two most common groups were the EAEC group (20.7%) and the EPEC group (13%).
The E. coli strains carrying virulence genes were resistant to many antibiotics with high rates: ampicillin (100%), cefotaxime (95.7%), streptomycine (82.9%), tetracycline (72.7%), and trimethoprim-sulfamethoxazol (72.9%).
However, there was no significant difference when comparing the resistant rate between E. coli strains carrying virulence genes and noncarrying virulence genes. Among the E. coli strains carrying virulence genes, the EAEC, EPEC, EAEC/DAEC and EAEC/EPEC groups all had a multidrug resistance rates from 94.2 to 100%, while the ETEC group had multidrug resistance rate was 42.9%. The multidrug resistance rate of ETEC group was significantly lower than those of other groups (p < 0.05).