TABLE 1.
Trends in resistance patterns among S. pneumoniae isolates in the SENTRY Antimicrobial Surveillance Program (1997–1999, North America)
| Antimicrobial agent | % of isolates susceptible (resistant) ina:
|
|
|---|---|---|
| 1997–1998 (3,854 strains) | 1999 (1,201 strains) | |
| Penicillin | 65.3–74.4 (7.5–13.5)b | 67.1 (14.9) |
| Erythromycin | 83.1–89.3 (9.8–15.9) | 75.4 (23.7)c |
| Ciprofloxacin | NA [1.7–2.4]d | NAe [2.0] |
| Levofloxacin | 99.1–99.6 (0.2–0.3) | 98.9 (0.9)c |
a
Susceptibility interpreted by NCCLS criteria (5).
b
Range of percentages indicates the minimal variations between Canada and U.S. results for 1997–1998, with a greater susceptibility usually found in Canada.
c
Significant increase in high-level resistance between the presented data samples (P < 0.05).
d
Values in brackets indicate the percentages of strains meeting the resistance criteria suggested by Chen et al. (1).
e
NA, no applicable criteria for susceptibility have been published by the NCCLS (5).