TABLE 3.
Phenotypic resistance of commensal E. coli isolates sampled across human vocation groupsa
| Antimicrobial | No. of E. coli isolates sampled by human vocation group (% of total)
|
P valueb | ||||
|---|---|---|---|---|---|---|
| Non-swine workers/ nonconsumers (n = 528) | Swine workers (n = 1,131) | Non-swine workers (n = 1,675) | Slaughter plant workers (n = 307) | Influent (mixed isolates) (n = 252) | ||
| Amikacin | 0 (0.0) | 0 (0.0) | 2 (0.1) | 0 (0.0) | 0 (0.0) | 0.497 |
| Amoxicillin-clavulanic acid | 29 (5.5) | 22 (2.0) | 41 (2.5) | 12 (3.9) | 5 (2.0) | 0.002 |
| Ampicillin | 135 (25.6) | 152 (13.4) | 245 (14.6) | 49 (16.0) | 42 (16.7) | <0.001 |
| Cefoxitin | 34 (6.4) | 17 (1.5) | 45 (2.7) | 16 (5.2) | 6 (2.4) | <0.001 |
| Ceftiofur | 0 (0.0) | 4 (0.4) | 7 (0.4) | 3 (1.0) | 0 (0.0) | 0.497 |
| Ceftriaxone | 0 (0.0) | 0 (0.0) | 2 (0.1) | 0 (0.0) | 0 (0.0) | 0.092 |
| Chloramphenicol | 9 (1.7) | 24 (2.1) | 27 (1.6) | 2 (0.7) | 2 (0.8) | 0.258 |
| Ciprofloxacin | 10 (1.9) | 8 (0.7) | 13 (0.8) | 0 (0.0) | 0 (0.0) | 0.005 |
| Gentamicin | 0 (0.0) | 6 (0.5) | 9 (0.5) | 5 (1.6) | 0 (0.0) | 0.012 |
| Kanamycin | 16 (3.0) | 12 (1.1) | 20 (1.2) | 11 (3.6) | 0 (0.0) | <0.001 |
| Nalidixic acid | 24 (4.6) | 54 (4.8) | 94 (5.6) | 1 (0.3) | 14 (5.6) | <0.001 |
| Streptomycin | 55 (10.4) | 100 (8.8) | 141 (8.4) | 38 (12.4) | 25 (9.9) | 0.209 |
| Sulfisoxazole | 67 (12.7) | 114 (10.1) | 224 (13.4) | 42 (13.7) | 31 (12.3) | 0.099 |
| Tetracycline | 98 (18.6) | 231 (20.4) | 300 (18.0) | 102 (33.2) | 57 (22.6) | <0.001 |
| Trimethoprim-sulfamethoxazole | 45 (8.5) | 74 (6.5) | 125 (7.5) | 33 (10.8) | 13 (5.2) | 0.069 |
a
Phenotypic resistance of commensal E. coli isolates from human wastewater samples (n = 3,893 isolates, with vocation cohorts identified). Frequencies and proportions are contrasted with human vocation cohorts across all unit locations and seasons.
b
P values are based on a likelihood ratio chi-square test of the differences in risk between human vocation cohorts. These P values are not adjusted for the dependence of responses within unit locations.