{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T12:47:54Z","timestamp":1770814074973,"version":"3.50.1"},"reference-count":33,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T00:00:00Z","timestamp":1770163200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"GECINA foundation"},{"name":"ARAPL Provence & Var NGO"},{"name":"Premed company"},{"name":"Soci\u00e9t\u00e9 Protectrice des Animaux NGO"},{"name":"Thellie plateform"},{"name":"Hopital Europ\u00e9en"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Dogs can detect volatile organic compounds (VOCs) associated with infectious diseases, but their ability to distinguish between symptomatic and asymptomatic SARS-CoV-2 infections has not been fully established. In this exploratory proof-of-concept study with a limited number of dogs, eight non-working dogs (without experience in scent detection) began training with either symptomatic or asymptomatic Delta samples; seven reached the testing phase and were then evaluated on the alternate group to assess cross-generalization. Training initially used a yes\/no protocol but was adapted to a line-up design after poor performance. When presented with novel Delta samples from the other category, dogs significantly discriminated them from controls, achieving a mean sensitivity of 71% and a specificity of 51%, with no difference between training groups. In contrast, performance dropped when dogs were tested with a small number of asymptomatic Omicron-positive samples from vaccinated individuals, with a mean sensitivity of 35% and a specificity of 55%. Dogs can thus generalize across symptomatic and asymptomatic COVID-19 cases for the Delta variant; performance decreased for Omicron samples, likely due to altered VOC profiles in vaccinated individuals. While proof-of-concept feasibility was demonstrated with a line-up protocol for detecting asymptomatic scent, detection dogs should not currently be recommended for large-scale screening; the findings underscore the need for standardized protocols and variant-specific retraining.<\/jats:p>","DOI":"10.3390\/ani16030480","type":"journal-article","created":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T12:51:56Z","timestamp":1770209516000},"page":"480","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Dogs\u2019 Detection of Symptomatic and Asymptomatic SARS-CoV-2 by Non-Working Dogs: Feasibility and Limits Under Controlled Laboratory Conditions"],"prefix":"10.3390","volume":"16","author":[{"given":"Jennifer","family":"Cattet","sequence":"first","affiliation":[{"name":"Center for the Study of Medical Alert Canines (CMAC), and Medical Mutts Service Dogs, 6120 Allisonville Rd, Indianapolis, IN 46220, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4997-1487","authenticated-orcid":false,"given":"Fr\u00e9d\u00e9rique","family":"Retornaz","sequence":"additional","affiliation":[{"name":"Unit\u00e9 de Soins et de Recherche en M\u00e9decine Interne et Maladies Infectieuses, H\u00f4pital Europ\u00e9en, 6 Rue D\u00e9sir\u00e9e Clary, 13003 Marseille, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Florine","family":"Munier","sequence":"additional","affiliation":[{"name":"Chiens d\u2019Assistance pour Diab\u00e9tiques Centre Domazane (ACADIA), 295 Chemin des Buis, 26250 Livron sur Dr\u00f4me, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Catherine","family":"Collignon","sequence":"additional","affiliation":[{"name":"Animalin Boutique, 173 Rue des Jardins, 32450 Aurimont, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7486-6200","authenticated-orcid":false,"given":"Florence","family":"Gaunet","sequence":"additional","affiliation":[{"name":"Centre de Recherche en Psychologie et Neurosciences (UMR 7077), Aix-Marseille University and CNRS, 3, Place Victor Hugo, 13003 Marseille, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Reeve, C., Wilson, C., Hanna, D., and Gadbois, S. 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