Enteropathogenic Escherichia coli in Psittaciformes

A total of 103 Escherichia coli isolates from psittaciform birds were exami ned for the presence of genes coding for shigatoxin 1 (Stx1), shigatoxin 2 (Stx2) and for intimin (eae), using the polymerase chain reaction (PCR), Si xty-eight E. coli strains were isolated from necropsy cases and faecal samp les, the other 35 were from 205 cloacal swabs from Psittaciformes with vari ous conditions. All isolates were tested for enterohaemorrhagic E. coli-hae molysin (Hly(EHEC)), some also for Stx production, but there was no geno-ty pic or phenotypic evidence of Stx in any of them. Seven isolates, six from birds with diarrhoea, harboured the eae gene, three of them belonging to th e O110:H6 serotype, one each to serotypes O153:H10, O131:H-, O63:H6 and Osp :H6. These seven eae-positive strains were negative for shigatoxin and Hly( EHEC), and the hly(EHEC) gene was not detectable by PCR. However, a PCR amp lifying the enteropathogenic E. coli (EPEC)-specific bundle-forming pill st ructural gene bfpA detected four bfpA positive strains (three of serotype O 110:H6, one O131:H-) among the seven eae positive strains, which classifies them as EPEC, Our findings suggest that shigatoxin-producing E. coli are u ncommon, but that EPEC should be considered as potential pathogens in psitt aciform birds, which may be a source of human EPEC infections.