Distribution and homology of foodborne-associated extendedspectrum β-lactamasesproducing Escherichia coli

Abstract:

ObjectiveTo study the distribution and homology of foodborneassociated extendedspectrum βlactamases (ESBLs)producing Escherichia coli (E. coli).MethodsESBLsproducing E. coli were isolated from different food specimens in Shaoguan from 2014 to 2015, strains were typed with pulsedfield gel electrophoresis (PFGE) and BioNumerics software.Results11 strains of diarrheacausing E. coli and 29 strains of ESBLsproducing E. coli were isolated from 347 different sources of food specimens. PFGE analysis showed that 29 strains could be divided into 21 cluster groups, group A was predominant pattern, which included 7 strains（J2, J3, J4, J7, J9, B4, S3）, group B included 2 strains (J6, J8), the other strains were sporadic clones. Similarity coefficient (SC) of 3 strains (J2, J7, J9) from health practitioners was 100%，SC of strains from drinking water and patients with diarrhea (B4) was 97.1%，SC of S3 strain and 4 strains (J2, J3, J7, J9) from health practitioners were all＞90.0%.ConclusionFoodborneassociated ESBLsproducing E. coli are widely distributed in food, water, animal, and populations, and can be transmitted through food chain, surveillance should enhanced to avoid further spread.