TABLE 1.
Comparison of the number of S. sonnei biotype g strains resistant to cotrimoxazole and ampicillin isolated during 2000 and 1997-1999
| Antibiotic | No. (%) of resistant strainsa
|
Pb | Relative risk | 95% confidence interval | |
|---|---|---|---|---|---|
| 2000 (n = 88) | 1997-1999 (n = 38) | ||||
| Cotrimoxazole | 83 (94) | 32 (84) | 0.08 | 1.12 | 0.967-1.297 |
| Ampicillin | 76 (86) | 6 (16) | <0.0001 | 5.47 | 2.612-11.454 |
a
Antibiotic susceptibilities were determined by the NCCLS method (16).
b
Probability was calculated by using Fisher's exact test.