Quantitative assessment of faecal shedding of β-lactam-resistant Escherichia coli and enterococci in dogs.
Quantitative data on faecal shedding of antimicrobial resistant bacteria are crucial to assess the risk of transmission from dogs to other animals as well as humans. In this study we investigated prevalence and concentrations of β-lactam-resistant Escherichia coli and enterococci in the faeces of 108 dogs presenting at a veterinary hospital in Denmark. The dogs had not been treated with antimicrobials for 4 weeks prior to the study. Total E. coli and enterococci were quantified by counts on MacConkey and Slanetz-Bartley, respectively. Resistant E. coli and enterococci were counted on the same media containing relevant antibiotic concentrations, followed by species identification using MALDI-TOF. Ampicillin- and cefotaxime-resistant E. coli were detected in 40% and 8% of the dogs, respectively, whereas approximately 15% carried ampicillin-resistant enterococci, mainly Enterococcus faecium. In the faeces of the carriers, the proportion of resistant strains in the total bacterial species population was on average 15% for both ampicillin-resistant E. coli (median faecal load 3.2×10(4)cfu/g) and E. faecium (5.8×10(2) cfu/g), and 4.6% for cefotaxime-resistant E. coli (8.6×10(3) cfu/g). Cefotaxime resistance was associated with the presence of blaCTX-M-1 (n=4), blaCMY-2 (n=4) or multiple mutations in the promoter and coding region of chromosomal ampC (n=1). Altogether the results indicate that the risks of zoonotic transmission of β-lactam-resistant bacteria via human exposure to canine faeces greatly vary amongst individual dogs and are influenced by unidentified factors other than recent antimicrobial use.
Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg C, Denmark.
Carmen
C
Espinosa-Gongora
Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg C, Denmark.
Syed Qaswar Ali
SQ
Shah
Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 16, 1870 Frederiksberg C, Denmark.
Lisbeth Rem
LR
Jessen
Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg C, Denmark.
Valeria
V
Bortolaia
Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 16, 1870 Frederiksberg C, Denmark.
Rikke
R
Langebæk
Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Dyrlægevej 16, 1870 Frederiksberg C, Denmark.
Charlotte Reinhard
CR
Bjørnvad
Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg C, Denmark. Electronic address: lg@sund.ku.dk.
Luca
L
Guardabassi
D000667:Ampicillin / Q000494:pharmacology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D057138:Bacterial Shedding; D002439:Cefotaxime / Q000494:pharmacology; D003718:Denmark; D004285:Dogs; D024881:Drug Resistance, Bacterial; D016984:Enterococcus faecium / Q000302:isolation & purification*; D004926:Escherichia coli / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D047090:beta-Lactams / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D000667:Ampicillin; D002439:Cefotaxime
Antibiotic resistance; Dogs; ESBL; Faeces