Distribution of Shigella Enterotoxins Genes and PFGE Molecular Typing of Shigella Strains in Tianjin

Objective To know the distribution of Shigella enterotoxins(ShET) genes,and the PFGE molecular typing of Shigella strains in Tianjin.Methods Three kinds of Shigella enterotoxin genes of 62 Shigella strains were detected by PCR;all strains were typed molecularly by pulsed field gel electrophoresis(PFGE).Results There were 36 strains of Shigella flexneri and 26 strains of Shigella sonnei within all Shigella strains;the positive rate of set1A,set1B and sen were,40.32%(25/62),40.32%(25/62)and 50%(31/62)in order.There was significant difference of enterotoxin genes distribution between Shigella flexneri and Shigella sonnei.All strains could be divided into 14 molecular types.Conclusion The prevalent Shigella strains in Tianjin were Shigella sonnei and Shigella flexneri from the year 2005 to 2007.The rate of Shigella sonnei grows up sharply years.Shigella sonnei strains isolated in Tianjin show a close relationship from 2005 to 2007,while Shigella flexneri comes from different clones.