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ARS Home » Midwest Area » Ames, Iowa » National Animal Disease Center » Virus and Prion Research » Research » Publications at this Location » Publication #401415

Research Project: Intervention Strategies to Control Endemic and New Emerging and Re-Emerging Viral Diseases of Swine

Location: Virus and Prion Research

Title: Experimental challenge of a SARS-CoV-2 Omicron variant in American mink

item Buckley, Alexandra
item Spackman, Erica
item Suarez, David
item Baker, Amy
item Lager, Kelly
item Palmer, Mitchell
item Cassmann, Eric

Submitted to: American Society for Virology Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 3/16/2023
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: During the global COVID-19 pandemic, there were reports of morbidity and mortality of farmed mink across Europe and the United States that tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Subsequently, research groups have experimentally challenged mink with SARS-CoV-2 and histologic reports have drawn comparisons between lesions observed in mink to those in humans; thus, making mink a useful animal model for COVID-19. The objective of this work was to document the pathogenesis of a contemporary SARS-CoV-2 isolate in mink. Eight American mink (Neovison vison) were intranasally challenged with 105.5 TCID50 of a SARS-CoV-2 omicron variant (B.1.1.529). Four mink served as controls. Animals were observed for clinical signs and temperature was measured daily. At 3, 6, 9, and 12 days post inoculation (dpi) two challenged and one control animal were euthanized and swabs, nasal wash, body weight, and tissues were collected. After challenge, no respiratory clinical signs or sustained increases in body temperature were observed, and weight loss, if present, was less than 5% of body weight. Swabs, nasal washes, and multiple tissues were PCR positive for animals necropsied on 3 and 6 dpi; however, most of these samples were negative on 9 and 12 dpi. Mink sacrificed at 3 and 6 dpi had mild to moderate neutrophilic rhinitis with loss of cilia, squamous metaplasia, and goblet cell hyperplasia in the rostral nasal cavity. Mink sacrificed at 9 and 12 dpi had similar lesions in addition to submucosal edema and lymphoplasmacytic infiltration. At early timepoints, lung lesions were characterized by vascular congestion, thickening of the alveolar septa, increased alveolar macrophages and perivascular lymphocytes, and type II pneumocyte hyperplasia. A better understanding of the pathogenesis of SARS-CoV-2 infection in mink could help define their role as a COVID-19 disease model and shape disease control measures for the mink industry.