Sniffing out safety: canine detection and identification of SARS-CoV-2 infection from armpit sweat.
Chris Callewaert, Maria Pezavant, Rony Vandaele, Bart Meeus, Ellen Vankrunkelsven, Phaedra Van Goethem, Alain Plumacker, Benoit Misset, Gilles Darcis, Sonia Piret, Lander De Vleeschouwer, Frank Staelens, Kristel Van Varenbergh, Sofie Tombeur, Anouck Ottevaere, Ilke Montag, Patricia Vandecandelaere, Stijn Jonckheere, Linos Vandekerckhove, Els Tobback, Gregoire Wieers, Jean-Christophe Marot, Kurt Anseeuw, Leen D'Hoore, Sebastiaan Tuyls, Brecht De Tavernier, Julie Catteeuw, Ali Lotfi, Alexey Melnik, Alexander Aksenov, Dominique Grandjean, Miguel Stevens, Frank Gasthuys, Hugues Guyot
Author Information
Chris Callewaert: Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
Maria Pezavant: Faculty of Veterinary Medicine, Clinique Vétérinaire Universitaire (CVU), University of Liège, Liège, Belgium.
Rony Vandaele: Federal Police Belgium, Linter, Belgium.
Bart Meeus: Federal Police Belgium, Linter, Belgium.
Ellen Vankrunkelsven: Federal Police Belgium, Linter, Belgium.
Phaedra Van Goethem: Federal Police Belgium, Linter, Belgium.
Anouck Ottevaere: General Hospital (AZ) Oudenaarde, Oudenaarde, Belgium.
Ilke Montag: Jan Yperman Hospital, Ypres, Belgium.
Patricia Vandecandelaere: Laboratory of Clinical Microbiology, Jan Yperman Hospital, Ypres, Belgium.
Stijn Jonckheere: Laboratory of Clinical Microbiology, Jan Yperman Hospital, Ypres, Belgium.
Linos Vandekerckhove: HIV Cure Research Center, Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent University, Ghent, Belgium.
Els Tobback: Department of General Internal Medicine and Infectious Diseases, Ghent University Hospital, Ghent, Belgium.
Gregoire Wieers: General Internal Medicine, Clinique Saint-Pierre Ottignies, Ottignies, Belgium.
Jean-Christophe Marot: General Internal Medicine, Clinique Saint-Pierre Ottignies, Ottignies, Belgium.
Kurt Anseeuw: Department of Emergency Medicine, ZNA, Antwerp, Belgium.
Brecht De Tavernier: Emergency Medicine and Intensive Care, GasthuisZusters (GZA) Hospital Group, Antwerp, Belgium.
Julie Catteeuw: General Hospital (AZ) Jan Palfijn, Ghent, Belgium.
Ali Lotfi: Department of Chemistry, University of Connecticut, Storrs, CT, United States.
Alexey Melnik: Department of Chemistry, University of Connecticut, Storrs, CT, United States.
Alexander Aksenov: Department of Chemistry, University of Connecticut, Storrs, CT, United States.
Dominique Grandjean: Nosaïs Program, Ecole Nationale Vétérinaire d'Alfort (Alfort School of Veterinary Medicine), University Paris-Est, Maisons-Alfort, France.
Miguel Stevens: Veterinary, Ypres, Belgium.
Frank Gasthuys: Department of Surgery, Anesthesiology and Orthopedics of Large Animals, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
Hugues Guyot: Faculty of Veterinary Medicine, Clinique Vétérinaire Universitaire (CVU), University of Liège, Liège, Belgium.
Detection dogs were trained to detect SARS-CoV-2 infection based on armpit sweat odor. Sweat samples were collected using cotton pads under the armpits of negative and positive human patients, confirmed by qPCR, for periods of 15-30 min. Multiple hospitals and organizations throughout Belgium participated in this study. The sweat samples were stored at -20°C prior to being used for training purposes. Six dogs were trained under controlled atmosphere conditions for 2-3 months. After training, a 7-day validation period was conducted to assess the dogs' performances. The detection dogs exhibited an overall sensitivity of 81%, specificity of 98%, and an accuracy of 95%. After validation, training continued for 3 months, during which the dogs' performances remained the same. Gas chromatography/mass spectrometry (GC/MS) analysis revealed a unique sweat scent associated with SARS-CoV-2 positive sweat samples. This scent consisted of a wide variety of volatiles, including breakdown compounds of antiviral fatty acids, skin proteins and neurotransmitters/hormones. An acceptability survey conducted in Belgium demonstrated an overall high acceptability and enthusiasm toward the use of detection dogs for SARS-CoV-2 detection. Compared to qPCR and previous canine studies, the detection dogs have good performances in detecting SARS-CoV-2 infection in humans, using frozen sweat samples from the armpits. As a result, they can be used as an accurate pre-screening tool in various field settings alongside the PCR test.
