TABLE 3.
Association within virulence factors and distribution according to the origin of the 220 STEC strains collected during this study
| Virulence factor genotypea | Distributionb
|
||||
|---|---|---|---|---|---|
| Overall (n = 220) | Cattle (n = 186) | Beef (n = 18) | Cheese (n = 6) | Children (n = 10) | |
| stx1 | 16 (7) | 4 (2) | 7 (39) | 2 (33) | 3 (30) |
| stx2 | 86 (39) | 79 (42.5) | 5 (28) | 0 (0) | 2 (20) |
| stx1-stx2 | 15 (7) | 13 (7) | 0 (0) | 1 (17) | 1 (10) |
| stx1-ehxA | 9 (4) | 8 (4.5) | 0 (0) | 0 (0) | 1 (10) |
| stx2-ehxA | 28 (13) | 24 (13) | 4 (22) | 0 (0) | 0 (0) |
| stx1-stx2-ehxA | 54 (24) | 49 (26.5) | 2 (11) | 3 (50) | 0 (0) |
| stx1-eae | 1 (0.5) | 0 (0) | 0 (0) | 0 (0) | 1 (10) |
| stx1-eae-ehxA | 8 (4) | 6 (3) | 0 (0) | 0 (0) | 2 (20) |
| stx2-eae-ehxA | 2 (1) | 2 (1) | 0 (0) | 0 (0) | 0 (0) |
| stx1-stx2-eae-ehxA | 1 (0.5) | 1 (0.5) | 0 (0) | 0 (0) | 0 (0) |
a
The number of stx-positive isolates was obtained by PCR and hybridization, and the numbers of eae- and ehxA-positive isolates were obtained by colony blot hybridization.
b
The number in parentheses indicates the percentage of positive isolates for the respective association.