RESUMO
Objective To analyze the molecular epidemiological characteristics of E. coli O 157∶H 7 of Xuzhou, Jiangsu. Methods The virulence gene spectrum of E. coli O 157∶H 7 strains were analyzed by PCR and the homology of E. coli O 157∶H 7 strains were detected by PFGE and RAPD. Results In all E. coli O 157∶H 7 strains isolated from epidemic area, 100% possess Hly and eaeA gene, 95.35% possess SLT 2 gene, and 11.63% possess SLT 1 gene. The PFGE spectrum showed that the strains isolated from epidemic area were distinctively different from the strains isolated from Japan, and similar to but not identical with the standard strain 882364. The PFGE spectrum of strains isolated from epidemic area patients were identical with those of strains isolated from excrements of poultries, domestic animals and insect intestine.Conclusions Poultries and domestic animals which carry E.coli O 157∶H 7 could be the source of infection. PFGE could be used to analyze E.coli O 157∶H 7 and played an important role in epidemiology study. The results showed that the method of analysis of E. coli O 157∶H 7 by RAPD was convenient and time saving.