Antimicrobial-Resistant Escherichia coli from Environmental Waters in Northern Colorado
Table 2
Percent resistance by E. coli to a panel of different antibiotics and across different water sources.
E. coli source
Drug class
Antibiotics
Sewer water () (%)
WWTP influent () (%)
Wastewater (sewer + influent) () (%)
WWTP effluent () (%)
Surface water () (%)
Ambient water (effluent + surface) () (%)
Aminoglycoside
Amikacin
0
0
0
0
0
0
Gentamicin
11.7
0
7.40
50.0
0
14.2
Tobramycin
5.88
0
3.70
50.0
0
14.2
Beta-lactam
Amoxicillin/clavulanic acid
29.4
40.0
33.3
50.0
0
14.2
Ampicillin
41.1
50.0
44.4
50.0
0
14.2
Cefalexin
35.2
40.0
37.0
50.0
0
14.2
Cefovecin
35.2
40.0
37.0
50.0
0
14.2
Cefpodoxine
35.2
40.0
37.0
50.0
0
14.2
Ceftiofur
23.5
40.0
29.6
50.0
0
14.2
Imipenem
29.4
40.0
33.3
50.0
0
14.2
Piperacillin
41.1
50.0
44.4
50.0
0
14.2
Chloramphenicol
Chloramphenicol
5.88
10.0
7.40
0
0
0
Fluoroquinolone
Marbofloxacin
11.7
0
7.40
0
0
0
Enrofloxacin
11.7
10.0
11.1
0
0
0
Nitrofuran
Nitrofurantoin
0
0
0
0
0
0
Tetracycline
Tetracycline
23.5
10.0
18.5
50.0
0
14.2
Sulfonamide
Trimethoprim/sulfamethoxazide
0
20.0
7.40
0
0
0
Percentage of E. coli isolates resistant to 17 drugs (5 drug classes) was calculated by dividing total E. coli resistant for a given drug by total E. coli examined in a source type. WWTP: wastewater treatment plant.
