A One Health Comparative Assessment of Antimicrobial Resistance in Generic and Extended-Spectrum Cephalosporin-Resistant <i>Escherichia coli</i> from Beef Production, Sewage and Clinical Settings

• Main Authors: Emelia H. Adator, Claudia Narvaez-Bravo, Rahat Zaheer, Shaun R. Cook, Lisa Tymensen, Sherry J. Hannon, Calvin W. Booker, Deirdre Church, Ron R. Read, Tim A. McAllister
• Format: Article
• Language: English
• Published: MDPI AG 2020-06-01
• Series: Microorganisms
• Subjects: antimicrobial resistance; extended-spectrum beta-lactamase (ESBL); one health; beef; sewage
• Online Access: https://www.mdpi.com/2076-2607/8/6/885
• ISSN: 2076-2607

This study aimed to compare antimicrobial resistance (AMR) in extended-spectrum cephalosporin-resistant and generic <i>Escherichia coli</i> from a One Health continuum of the beef production system in Alberta, Canada. A total of 705 extended-spectrum cephalosporin-resistant <i>E. coli</i> (ESC^r) were obtained from: cattle feces (CFeces, <i>n</i> = 382), catch basins (CBasins, <i>n</i> = 137), surrounding streams (SStreams, <i>n</i> = 59), beef processing plants (BProcessing, <i>n</i> = 4), municipal sewage (MSewage; <i>n</i> = 98) and human clinical specimens (CHumans, <i>n</i> = 25). Generic isolates (663) included: CFeces (<i>n</i> = 142), CBasins (<i>n</i> = 185), SStreams (<i>n</i> = 81), BProcessing (<i>n</i> = 159) and MSewage (<i>n</i> = 96). All isolates were screened for antimicrobial susceptibility to 9 antimicrobials and two clavulanic acid combinations. In ESC^r<i>,</i> oxytetracycline (87.7%), ampicillin (84.4%) and streptomycin (73.8%) resistance phenotypes were the most common, with source influencing AMR prevalence (<i>p</i> < 0.001). In generic <i>E. coli,</i> oxytetracycline (51.1%), streptomycin (22.6%), ampicillin (22.5%) and sulfisoxazole (14.3%) resistance were most common. Overall, 88.8% of ESC^r, and 26.7% of generic isolates exhibited multi-drug resistance (MDR). MDR in ESC^r was high from all sources: CFeces (97.1%), MSewage (96.9%), CHumans (96%), BProcessing (100%), CBasins (70.5%) and SStreams (61.4%). MDR in generic <i>E. coli</i> was lower with CFeces (45.1%), CBasins (34.6%), SStreams (23.5%), MSewage (13.6%) and BProcessing (10.7%). ESBL phenotypes were confirmed in 24.7% (<i>n</i> = 174) ESC^r and 0.6% of generic <i>E. coli</i>. Prevalence of <i>bla</i> genes in ESC^r were <i>bla</i>_CTXM (30.1%), <i>bla</i>_CTXM-1 (21.6%), <i>bla</i>_TEM (20%), <i>bla</i>_CTXM-9 (7.9%), <i>bla</i>_OXA (3.0%), <i>bla</i>_CTXM-2 (6.4%), <i>bla</i>_SHV (1.4%) and AmpC β-lactamase <i>bla</i>_CMY (81.3%). The lower AMR in ESC^r from SStreams and BProcessing and higher AMR in CHumans and CFeces likely reflects antimicrobial use in these environments. Although MDR levels were higher in ESC^r as compared to generic <i>E. coli</i>, AMR to the same antimicrobials ranked high in both ESC^r and generic <i>E. coli</i> sub-populations. This suggests that both sub-populations reflect similar AMR trends and are equally useful for AMR surveillance. Considering that MDR ESC^r MSewage isolates were obtained without enrichment, while those from CFeces were obtained with enrichment, MSewage may serve as a hot spot for MDR emergence and dissemination.