Volume 23, Number 1—January 2017
Research
Estimated Incidence of Antimicrobial Drug–Resistant Nontyphoidal Salmonella Infections, United States, 2004–2012
, Weidong Gu, Barbara Mahon, Michael Judd, Jason P. Folster, Patricia M. Griffin, and Robert M. Hoekstra
Table 1
Nontyphoidal Salmonella isolates with clinically important resistance, by serotype and resistance category, United States, 2004–2012*
| Resistance category | Typhimurium, no. (%), n = 3,324 | Enteritidis, no. (%), n = 3,501 | Newport, no. (%), n = 2,175 | Heidelberg, no. (%), n = 738 | Other fully serotyped, no. (%), n = 9,265 | Not fully serotyped, no. (%), n = 407 | Total NTS, no. (%), n = 19,410 |
|---|---|---|---|---|---|---|---|
| Cipro† | 54 (1.6) | 211 (6.0) | 7 (0.3) | 2 (0.3) | 183 (2.0) | 10 (2.5) | 467 (2.4) |
| Cef/Amp‡ | 162 (4.9) | 8 (0.2) | 198 (9.1) | 87 (11.8) | 141 (1.5) | 3 (0.7) | 599 (3.1) |
| Amp-only§ | 750 (22.6) | 90 (2.6) | 25 (1.1) | 94 (12.7) | 274 (3.0) | 21 (5.2) | 1,254 (6.5) |
| Any of the above¶ | 966 (29.1) | 309 (8.8) | 230 (10.6) | 183 (24.8) | 598 (6.5) | 34 (8.4) | 2,320 (12.0) |
*Total NTS isolates include isolates serotyped as Typhimurium, Enteritidis, Newport, and Heidelberg; isolates serotyped as other than these 4; and those not fully serotyped. Amp-only, resistant to ampicillin but susceptible to ceftriaxone and ciprofloxacin; Cef/Amp, resistant to ceftriaxone and ampicillin; Cipro, nonsusceptible to ciprofloxacin but susceptible to ceftriaxone; NTS, nontyphoidal Salmonella. Cipro, Cef/Amp, and Amp-only are mutually exclusive categories.
†Nonsusceptible to ciprofloxacin (MIC >0.12 μg/mL) but susceptible to ceftriaxone, with or without resistance to other agents.
‡Resistant to ceftriaxone (MIC ≥4 μg /mL) and ampicillin (MIC ≥32 μg /mL), with or without nonsusceptibility to ciprofloxacin or resistance to other agents; of the 599 ceftriaxone-resistant isolates, 38 (0.2% of all NTS isolates) were nonsusceptible to ciprofloxacin.
§Resistant to ampicillin but susceptible to ceftriaxone and ciprofloxacin, with or without resistance to other agents.
¶Nonsusceptible to ciprofloxacin, resistant to ceftriaxone, or resistant to ampicillin.