TABLE 3.
Distribution of antimicrobial resistance genes detected in ETEC O149:K91 isolates by isolation period
| Antimicrobial to which resistance was detected | Antimicrobial resistance probe | No. (%)a of positive isolates by isolation period
|
||||
|---|---|---|---|---|---|---|
| 1978-1984 | 1985-1989 | 1990-1994 | 1995-2000 | Total | ||
| Ampicillin | blaTEM | 8 (100) | 1 (50) | 3 (38) | 25 (100) | 37 (86) |
| blaSHV | 3 (38) | 0 (0) | 1 (12) | 5 (20) | 9 (21) | |
| blaOXA-1 | 0 (0) | 0 (0) | 2 (25) | 0 (0) | 2 (5) | |
| blaOXA-7, blaPSE, blaCTX-M-3 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Gentamicin | aac(3)-IV | 0 (0) | 0 (0) | 1 (100) | 11 (92) | 12 (75) |
| ant(2")-Ia, aac(3)-IIa | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Neomycin | aph(3′)-Ia | 9 (90) | 4 (80) | 4 (100) | 17 (85) | 34 (87) |
| aph(3′)-IIa | 1 (10) | 1 (20) | 2 (50) | 2 (10) | 6 (15) | |
| ant(2")-Ia | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Kanamycin | aph(3′)-Ia | 9 (90) | 4 (67) | 4 (50) | 17 (89) | 34 (79) |
| aph(3′)-IIa | 1 (10) | 2 (33) | 3 (38) | 2 (10) | 8 (19) | |
| ant(2")-Ia | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Tetracycline | tet(A) | 1 (4) | 1 (4) | 3 (14) | 21 (54) | 26 (25) |
| tet(B) | 21 (95) | 23 (100) | 19 (90) | 20 (51) | 83 (80) | |
| tet(C) | 1 (4) | 1 (4) | 3 (14) | 21 (54) | 26 (25) | |
| tet(D), tet(E), tet(Y) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Chloramphenicol | catI | 4 (100) | 1 (100) | 2 (100) | 12 (70) | 19 (79) |
| catII, catIII, floR | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Trimethoprim | dhfrI | 0 (0) | 2 (100) | 0 (0) | 4 (16) | 6 (20) |
| dhfrV | 0 (0) | 0 (0) | 0 (0) | 14 (56) | 14 (47) | |
| dhfrXIII | 0 (0) | 0 (0) | 2 (100) | 7 (28) | 9 (30) | |
| dhfrVII, dhfrIX | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Sulfonamides | sulI | 18 (82) | 20 (83) | 21 (95) | 22 (65) | 81 (79) |
| sulII | 8 (36) | 7 (29) | 3 (14) | 19 (56) | 37 (36) | |
a
Percentage of probe-positive isolates among resistant ETEC isolates by period.