Marti, I. | Search bioRxiv

bioRxiv2025

Antimicrobial Resistance in Wildlife across Switzerland and the Principality of Liechtenstein: Associations with Environmental Factors and Taxonomic Variation

Antimicrobial resistance (AMR) presents a significant challenge to global public health. Addressing this challenge requires a comprehensive One Health approach that integrates efforts in human, veterinary, and environmental domains. Whereas AMR research in medical and veterinary domains is extensive, AMR research in wildlife has received less attention. However, AMR prevalence in the environment, and specifically in wildlife, ultimately affects human life. In a large study conducted in Switzerland and the Principality of Liechtenstein, we collected 410 rectal swab samples from 37 different wildlife species to quantify the prevalence of Escherichia coli (E. coli) and its resistance to 16 antimicrobial drugs, determined through phenotypical antimicrobial susceptibility testing. The study yielded an 81.5% E. coli isolation rate with a considerable 10.8% of isolates resistant to one or more antimicrobial drugs. Notably, 4.5% of the isolates demonstrated multidrug resistance (MDR). Furthermore, we found that E. coli in omnivores exhibited the highest levels of AMR, significantly higher than in carnivores and herbivores. In addition to these dietary associations, we found that the percentage of forested areas surrounding the sampling locations was inversely related to AMR rates, suggesting that environmental conditions play a role in mitigating AMR. This study provides a large-scale quantification of AMR in a broad range of wildlife species and also identifies diverse patterns of AMR in E. coli, highlighting variations associated with both host species and environmental conditions. Our findings emphasize the role of wildlife as potential indicators of environmental contamination with antibiotics and as reservoirs of resistant bacteria.

microbiology↗

bioRxiv2023

Analysis of a European general wildlife health surveillance program: chances, challenges and recommendations

In the context of a One Health perspective general wildlife health surveillance (GWHS) gains importance worldwide, as pathogen transmission among wildlife, domestic animals and humans raises health, conservation and economic concerns. However, GWHS programs operate in the face of legal, geographical, financial, or administrative conditions. The present study uses a multi-tiered approach to understand the current characteristics, strengths and gaps of a European GWHS that operates in a fragmented legislative and multi-stakeholder environment. The aim is to support the implementation or improvement of other GWHS systems by managers, surveillance experts, and administrations. To assess the current state of wildlife health investigations and trends within the GWHS, we analyzed 20 years of wildlife diagnostic data, conducted an online survey and phone interviews with official field partners (hunting administrators, game wardens and hunters), and performed a time-per-task analysis. Firstly, we found that infectious disease dynamics, the level of public awareness for specific diseases, research activities and increasing population sizes of in depth-monitored protected species, together with biogeographical and political boundaries all impacted case numbers and can present unexpected challenges to a GWHS. Secondly, we found that even a seemingly comprehensive GWHS can feature pronounced information gaps, with underrepresentation of common or easily recognizable diseases, blind spots in non-hunted species and only a fraction of discovered carcasses being submitted. Thirdly, we found that substantial amounts of wildlife health data may be available at local hunting administrations or disease specialist centers, but outside the reach of the GWHS and its processes. In conclusion, we recommend that fragmented and federalist GWHS programs like the one addressed require a central, consistent and accessible collection of wildlife health data. Also, considering the growing role of citizen observers in environmental research, we recommend using online reporting systems to harness decentrally available information and fill wildlife health information gaps.

zoology↗