Volume 26, Number 4—April 2020
Synopsis
Decreased Susceptibility to Azithromycin in Clinical Shigella Isolates Associated with HIV and Sexually Transmitted Bacterial Diseases, Minnesota, USA, 2012–2015
Table 1
Frequency of azithromycin zone of inhibition for Shigella isolates by species, Minnesota, USA, 2012–2015*
Inhibition zone, mm | No. (%) isolates |
|||
---|---|---|---|---|
S. sonnei, n = 559 | S. flexneri, n = 125† | S. boydi, n = 5 | S. dysenteriae, n = 2 | |
6 | 24 (4) | 18 (14) | 1 (20) | 0 |
8 | 0 | 1 (0.8) | 0 | 0 |
12 | 0 | 1 (0.8) | 0 | 0 |
14 | 0 | 1 (0.8) | 0 | 0 |
15 | 1 (0.2) | 0 | 0 | 0 |
17 | 2 (0.4) | 0 | 0 | 0 |
18 | 3 (1) | 0 | 0 | 0 |
19 | 5 (1) | 2 (2) | 0 | 0 |
20 | 23 (4) | 4 (3) | 0 | 0 |
21–25 | 442 (79) | 48 (38) | 2 (40) | 1 (50) |
26–30 | 58 (10) | 44 (35) | 2 (40) | 0 |
>30 | 1 (0.2) | 6 (5) | 0 | 1 (50) |
*Decreased susceptibility to azithromycin is defined as no zone of inhibition (6 mm) by disk diffusion using a disk containing 15 µg of azithromycin.
†Decreased susceptibility to azithromycin is defined as a <15 mm zone of inhibition with a disk containing 15 µg of azithromycin.