Table 2. Antibiotic Resistance of Campylobacter jejuni Isolates Associated With Pet Store Puppies (2011-2020) and Surveillance Isolates From the National Antimicrobial Resistance Monitoring System (2011-2019)a.
| Agent | No. (%) of cases | |||
|---|---|---|---|---|
| All isolates linked to pet store puppies (February 1, 2011, to February 29, 2020) (N = 191)b | Investigation 1 (January 1, 2016, to February 29, 2018) (n = 62) | Investigation 2 (January 1, 2019, to February 29, 2020) (n = 44) | NARMS surveillance (January 1, 2011, to December 31, 2019) (N = 9358)c | |
| Antimicrobial class | ||||
| Quinolones | 181 (95) | 62 (100) | 39 (89) | 2441 (26) |
| Lincosamides | 176 (92) | 62 (100) | 39 (89) | 617 (6.6) |
| Macrolides | 176 (92) | 62 (100) | 39 (89) | 200 (2) |
| Phenicolsc | 13 (18) | 10 (30) | 2 (8) | 105 (1) |
| Aminoglycosides | 150 (79) | 53 (85) | 32 (73) | 113 (1) |
| Ketolides | 174 (91) | 62 (100) | 38 (86) | 201 (2) |
| Tetracyclines | 191 (100) | 62 (100) | 44 (100) | 4404 (47) |
| XDRd | 168 (88) | 62 (100) | 34 (77) | 126 (1) |
Abbreviation: NARMS, National Antimicrobial Resistance Monitoring System; XDR, extensively drug resistant.
Antibiotic resistance was determined based on results of antibiotic susceptibility testing when available; otherwise, resistance was determined by the presence of resistance determinants in bacterial genomes. This table includes only antibiotic classes for which phenotypic antibiotic susceptibility testing was performed.
Total includes isolates from 48 patients from investigation 1, 41 patients from investigation 2, 45 patients from enhanced surveillance (February 1 to December 31, 2018), 31 patients from retrospective case finding (before 2016), and 22 isolates from dogs. Antibiotic resistance was determined by antibiotic susceptibility testing for 73 isolates.
The NARMS routine surveillance is based on antibiotic susceptibility testing of a subset of isolates from 10 public health laboratories in the FoodNet sites.19 During 2011 to 2019, isolates were selected for testing using a frequency-based sampling approach.3 These data are based on results of phenotypic antibiotic susceptibility testing only.
Defined as resistance to macrolides and fluoroquinolones and 3 or more antibiotic classes.