Table 2.
Distribution, according to the different socioeconomic strata, of virulence markers and antimicrobial susceptibility patterns of Shiga toxin-producing Escherichia coli isolated from ground beef in Buenos Aires, Argentina.
| Strata | Proportion of STEC | Genotype | Phenotype | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| stx1 | stx1 and stx2 | stx2 | eae | saa | ehxA | Serogroup | Antimicrobial susceptibility* | EHEC-Hly** | ||||||
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | O157 | Non-O157*** | S | R | R and r | r | n (%) | ||
| n (%) | n (%) | n (%) | n (%) | n (%) | n (%) | |||||||||
| High | 13/77 | 0 (0) |
2 (13.3) |
11 (84.6) |
1 (7.7) |
4 (30.8) |
7 (53.8) |
1 (7.7) |
12 (92.3) |
4 (30.8) |
2 (13.3) |
3 (23.1) |
4 (30.8) |
7 (53.8) |
| Media | 25/91 | 3 (12) |
1 (0.64) |
21 (84.0) |
8 (32.0) |
3 (12) |
15 (60.0) |
5 (20.0) |
20 (80.0) |
10 (40.0) |
3 (12) |
4 (16.0) |
8 (32.0) |
7 (28.0) |
| Low | 19/84 | 0 (0) |
2 (10.5) |
17 (89.5) |
6 (31.6) |
7 (36.8) |
13 (68.4) |
5 (26.3) |
14 (73.7) |
9 (47.4) |
0 (0) |
4 (21) |
6 (31.6) |
11 (57.9) |
|
| ||||||||||||||
| Total | 57/252 | 3 (5.3) |
5 (8.8) |
49 (86.0) |
15 (26.3) |
14 (24.6) |
35 (61.4) |
11 (19.3) |
46 (80.7) |
23 (40.3) |
5 (8.8) |
11 (19.3) |
18 (31.6) |
25 (43.9) |
*Susceptibility patterns: S: susceptible, R: resistant, r: intermediate or reduced susceptible strains.
**The alfa-hemolytic strain belonging to media strata is not included.
***Non-O157 include serogroups OR and ONT.