What does the fox say? Monitoring antimicrobial resistance in the environment using wild red foxes as an indicator.

PLoS One 2018 25;13(5):e0198019. Epub 2018 May 25.

Norwegian Veterinary Institute, Sentrum, Oslo, Norway.

The objective of this study was to estimate and compare the occurrence of AMR in wild red foxes in relation to human population densities. Samples from wild red foxes (n = 528) included in the Norwegian monitoring programme on antimicrobial resistance in bacteria from food, feed and animals were included. All samples were divided into three different groups based on population density in the municipality where the foxes were hunted. Of the 528 samples included, 108 (20.5%), 328 (62.1%) and 92 (17.4%) originated from areas with low, medium and high population density, respectively. A single faecal swab was collected from each fox. All samples were plated out on a selective medium for Enterobacteriaceae for culturing followed by inclusion and susceptibility testing of one randomly selected Escherichia coli to assess the overall occurrence of AMR in the Gram-negative bacterial population. Furthermore, the samples were subjected to selective screening for detection of E. coli displaying resistance towards extended-spectrum cephalosporins and fluoroquinolones. In addition, a subset of samples (n = 387) were subjected to selective culturing to detect E. coli resistant to carbapenems and colistin, and enterococci resistant to vancomycin. Of these, 98 (25.3%), 200 (51.7%) and 89 (23.0%) originated from areas with low, medium and high population density, respectively. Overall, the occurrence of AMR in indicator E. coli from wild red foxes originating from areas with different human population densities in Norway was low to moderate (8.8%). The total occurrence of AMR was significantly higher; χ2 (1,N = 336) = 6.53, p = 0.01 in areas with high population density compared to areas with medium population density. Similarly, the occurrence of fluoroquinolone resistant E. coli isolated using selective detection methods was low in areas with low population density and more common in areas with medium or high population density. In conclusion, we found indications that occurrence of AMR in wild red foxes in Norway is associated with human population density. Foxes living in urban areas are more likely to be exposed to AMR bacteria and resistance drivers from food waste, garbage, sewage, waste water and consumption of contaminated prey compared to foxes living in remote areas. The homerange of red fox has been shown to be limited thereby the red fox constitutes a good sentinel for monitoring antimicrobial resistance in the environment. Continuous monitoring on the occurrence of AMR in different wild species, ecological niches and geographical areas can facilitate an increased understanding of the environmental burden of AMR in the environment. Such information is needed to further assess the impact for humans, and enables implementation of possible control measures for AMR in humans, animals and the environment in a true "One Health" approach.

Abstract Video

New in Open Access - 6/22/2018

Source: Research Square

Download full-text PDF

November 2018
783 Reads

Publication Analysis

Top Keywords

population density
occurrence amr
wild red
red foxes
high population
areas low
amr wild
antimicrobial resistance
human population
medium high
foxes living
subjected selective
low medium
density occurrence
areas medium
red fox


(Supplied by CrossRef)
The evolving threat of antimicrobial resistance: Options for action
G Dziekan et al.
Guide to antimicrobial use in animals
L Guardabassi et al.
Antibiotic resistance is the quintessential One Health issue
TP Robinson et al.
Trans R Soc Trop Med Hyg 2016
Tackling antibiotic resistance: the environmental framework
TU Berendonk et al.
Nat Rev Microbiol 2015
Antimicrobial resistance in bacteria of animal origin
L Guardabassi et al.
Technical specifications on randomised sampling for harmonised monitoring of antimicrobial resistance in zoonotic and commensal bacteria
EFSA journal 2014

Similar Publications