TABLE 2.
Detection of combinations of EHEC-associated genetic markers in cattle feces and isolation of E. coli strains belonging to the five targeted serogroups
| EHEC-associated genetic marker(s) detected in cattle feces | No. of samples with indicated marker(s) (% of positive samples) | No. of positive samples/no. of tested samplesa |
|
|---|---|---|---|
| Putative serogroupb | Confirmed serogroupc | ||
| stx + eae + O | 143d (na) | ||
| eae subtype+ | 46d (na) | 27/46 | 22/27 |
| eae subtype− | 97d (na) | 20/39e | 2/20 |
| stx + eae + ihp1O145 | 77 (51.3) | ||
| eae-γ1+ | 16 (10.7) | 1/16 | 1/1 |
| eae-γ1− | 61 (40.7) | 2/3e | 1/2 |
| stx + eae + wzxO103 | 25 (16.7) | ||
| eae-ε+ | 5 (3.3) | 5/5 | 1/5 |
| eae-ε− | 20 (13.3) | 14/20 | 0/14 |
| stx + eae + wzxO26 | 23 (15.3) | ||
| eae-β1+ | 18 (12.0) | 14/18 | 13/14 |
| eae-β1− | 5 (3.3) | 3/5 | 1/3 |
| stx + eae + rfbEO157 | 16 (10.7) | ||
| eae-γ1+ | 7 (4.7) | 7/7 | 7/7 |
| eae-γ1− | 9 (6.0) | 0/9 | |
| stx + eae + wbd1O111 | 2 (1.3) | ||
| eae-θ+ | 0 (0.0) | ||
| eae-θ− | 2 (1.3) | 1/2 | 0/1 |
a
Data represent the number of positive samples resulting in isolation of strains belonging to the indicated serogroup(s)/number of tested samples.
b
The putative serogroup of isolates was determined by slide agglutination with specific antisera.
c
The confirmed serogroup of the isolates was determined by PCR.
d
Several samples contained combinations of two or more EHEC-associated genetic markers. na, not applicable.
e
Of the 61 samples positive for the combination of stx plus eae plus ihp1O145 and negative for eae-γ1, only 3 have been subjected to the isolation procedure.