Four Novel SARS-CoV-2 Infected Feral American Mink (Neovison Vison) Among 60 Individuals Caught in the Wild

TL;DR

This study found limited SARS-CoV-2 infections in wild American mink in Spain, highlighting the need for wildlife monitoring to prevent zoonotic disease spread.

Contribution

The study expands on prior findings by testing 60 additional feral mink and confirms limited SARS-CoV-2 circulation in wild populations.

Findings

Only 6 out of 73 feral mink tested positive for SARS-CoV-2, indicating low prevalence.

Infected mink had low viral loads and clustered with B.1.177 and Alpha variants.

Wild mink showed seasonal breeding and high population turnover, similar to other populations.

Abstract

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, raised awareness of the role animals can play in the spread of infectious diseases. Mink are highly susceptible to this virus and can transmit it to other mink and humans. In this study, we tested 60 wild-living (feral) American mink captured in eastern Spain to detect possible SARS-CoV-2 infections. We found four positive animals. Combined with a previous pilot study that detected 2 infected mink among 13, only 6 out of 73 animals tested positive. This finding indicates that while infection can occur in the wild, the overall prevalence remains low. We also analyzed the body condition and reproductive status of the mink, which showed seasonal breeding and high population turnover, consistent with other wild mink populations. These results suggest limited spread of SARS-CoV-2 in feral mink and highlight the importance of continued monitoring of wildlife to detect emerging diseases that may affect both animals and humans.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the zoonotic virus responsible for the COVID-19 pandemic, has caused global health and economic disruption. American mink (Neovison vison) are highly susceptible to SARS-CoV-2 and capable of transmitting it to both mink and humans. We previously reported the first detection of SARS-CoV-2 in feral mink, with two positive cases among 13 animals in the upper courses of two rivers in the Valencian Community, eastern Spain. Here, we expand that study with 60 additional feral mink sampled from November 2020 to May 2022. Four new positives were identified by two-step RT-PCR assay on necropsy samples, including nasal and rectal swabs, lung tissue, lymph nodes, and fetuses from three pregnant females. In total, six of 73 mink tested positive, all with low viral loads. Sanger sequencing confirmed infection and revealed clustering with the B.1.177 and Alpha variants. Body weight and reproductive status analyses indicated seasonal breeding and high population turnover, consistent with other wild mink populations. Our findings reveal that SARS-CoV-2 circulation is limited in feral mink, at least in this region. They underscore the key importance of wildlife surveillance as an element of the One Health strategy, which encompasses humans, animals, and the environment.

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