{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,6]],"date-time":"2025-11-06T12:30:10Z","timestamp":1762432210122,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,2,28]],"date-time":"2022-02-28T00:00:00Z","timestamp":1646006400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Boehringer Ingelheim Animal Health","award":["2021"],"award-info":[{"award-number":["2021"]}]},{"name":"Center for Equine Health, School of Veterinary Medicine, University of California, Davis, California, USA","award":["2021"],"award-info":[{"award-number":["2021"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>More and more studies are reporting on the natural transmission of SARS-CoV-2 between humans with COVID-19 and their companion animals (dogs and cats). While horses are apparently susceptible to SARS-CoV-2 infection based on the homology between the human and the equine ACE-2 receptor, no clinical or subclinical infection has yet been reported in the equine species. To investigate the possible clinical role of SARS-CoV-2 in equids, nasal secretions from 667 horses with acute onset of fever and respiratory signs were tested for the presence of SARS-CoV-2 by qPCR. The samples were collected from January to December of 2020 and submitted to a commercial molecular diagnostic laboratory for the detection of common respiratory pathogens (equine influenza virus, equine herpesvirus-1\/-4, equine rhinitis A and B virus, Streptococcus equi subspecies equi). An additional 633 serum samples were tested for antibodies to SARS-CoV-2 using an ELISA targeting the receptor-binding domain of the spike protein. The serum samples were collected from a cohort of 587 healthy racing Thoroughbreds in California after track personnel tested qPCR-positive for SARS-CoV-2. While 241\/667 (36%) equids with fever and respiratory signs tested qPCR-positive for at least one of the common respiratory pathogens, not a single horse tested qPCR-positive for SARS-CoV-2. Amongst the racing Thoroughbreds, 35\/587 (5.9%) horses had detectable antibodies to SARS-CoV-2. Similar to dogs and cats, horses do not seem to develop clinical SARS-CoV-2 infection. However, horses can act as incidental hosts and experience silent infection following spillover from humans with COVID-19. SARS-CoV-2-infected humans should avoid close contact with equids during the time of their illness.<\/jats:p>","DOI":"10.3390\/ani12050614","type":"journal-article","created":{"date-parts":[[2022,2,28]],"date-time":"2022-02-28T20:09:57Z","timestamp":1646078997000},"page":"614","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Investigation of the Role of Healthy and Sick Equids in the COVID-19 Pandemic through Serological and Molecular Testing"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2453-0850","authenticated-orcid":false,"given":"Kaila O. Y.","family":"Lawton","sequence":"first","affiliation":[{"name":"Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rick M.","family":"Arthur","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University of California, Davis, CA 95616, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2945-3620","authenticated-orcid":false,"given":"Benjamin C.","family":"Moeller","sequence":"additional","affiliation":[{"name":"KL Maddy Equine Analytical Chemistry Laboratory, School of Veterinary Medicine, University of California, Davis, CA 95616, USA"},{"name":"Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Samantha","family":"Barnum","sequence":"additional","affiliation":[{"name":"Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicola","family":"Pusterla","sequence":"additional","affiliation":[{"name":"Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1678","DOI":"10.7150\/ijbs.45053","article-title":"SARS-CoV-2: An emerging coronavirus that causes a global threat","volume":"16","author":"Zheng","year":"2020","journal-title":"Int. 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