Table 2. Distribution of hha2 and hha3 genes among E. coli strains belonging to different pathotypes.

Pathotype	Number of strains analysed	Number and percentage of strains containing only allele hha-2	Number and percentage of strains containing only allele hha-3	Number and percentage of strains containing both alleles hha-2 and hha-3
EAEC	16	2 (12.5%)	0	8 (50%)
ExPEC	14	3 (21%)	1 (7%)	4 (29%)
ExPEC ST131	6	1 (17%)	1 (17%)	3 (50%)
ExPEC no-ST131	8	2 (25%)	0 (0%)	1 (13%)
STEC/VTEC	21	3 (14%)	1 (5%)	6 (29%)
ETEC	3	2 (67%)	1 (33%)	0 (0%)
tEPEC	2	0 (0%)	0 (0%)	1 (50%)
EIEC	2	0 (0%)	0 (0%)	0 (0%)
AIEC	1	0 (0%)	0 (0%)	0 (0%)