Scent dog identification of SARS-CoV-2 infections in different body fluids
Paula Jendrny, Friederike Twele, Sebastian Meller, Claudia Schulz, Maren von Köckritz‐Blickwede, Albertus Dominicus Marcellinus Eras Osterhaus, Hans Ebbers, Janek Ebbers, Veronika Pilchová, Isabell Pink, Tobias Welte, Michael P. Manns, Anahita Fathi, Marylyn M. Addo, Christiane Ernst, Wencke Schäfer, Michael Engels, A. A. Petrov, Katharina Marquart, Ulrich Schotte, Esther Schalke, Holger A. Volk
Abstract
BACKGROUND: The main strategy to contain the current SARS-CoV-2 pandemic remains to implement a comprehensive testing, tracing and quarantining strategy until vaccination of the population is adequate. Scent dogs could support current testing strategies. METHODS: Ten dogs were trained for 8 days to detect SARS-CoV-2 infections in beta-propiolactone inactivated saliva samples. The subsequent cognitive transfer performance for the recognition of non-inactivated samples were tested on three different body fluids (saliva, urine, and sweat) in a randomised, double-blind controlled study. RESULTS: Dogs were tested on a total of 5242 randomised sample presentations. Dogs detected non-inactivated saliva samples with a diagnostic sensitivity of 84% (95% CI: 62.5-94.44%) and specificity of 95% (95% CI: 93.4-96%). In a subsequent experiment to compare the scent recognition between the three non-inactivated body fluids, diagnostic sensitivity and specificity were 95% (95% CI: 66.67-100%) and 98% (95% CI: 94.87-100%) for urine, 91% (95% CI: 71.43-100%) and 94% (95% CI: 90.91-97.78%) for sweat, 82% (95% CI: 64.29-95.24%), and 96% (95% CI: 94.95-98.9%) for saliva respectively. CONCLUSIONS: The scent cognitive transfer performance between inactivated and non-inactivated samples as well as between different sample materials indicates that global, specific SARS-CoV-2-associated volatile compounds are released across different body secretions, independently from the patient's symptoms. All tested body fluids appear to be similarly suited for reliable detection of SARS-CoV-2 infected individuals.