Detection of SARS-CoV-2 by Canine Olfaction: A Pilot Study

Area of Science:

• Infectious Diseases
• Veterinary Medicine
• Analytical Chemistry

Background:

• The global surge in COVID-19 cases and emergence of new variants necessitate rapid, noninvasive diagnostic tools.
• Current SARS-CoV-2 detection methods are often costly, invasive, and time-consuming, with global vaccination disparities persisting.
• Volatile organic compounds (VOCs) in bodily fluids of infected individuals are detectable by canine olfaction, suggesting potential for medical detection dogs.

Purpose of the Study:

• To validate the efficacy of medical detection dogs as a feasible, accurate, and affordable screening method for SARS-CoV-2.
• To assess the diagnostic performance of trained dogs in identifying SARS-CoV-2 in human sweat samples.

Main Methods:

• A double-blinded, case-control validation study involving sweat sample collection from 584 inpatients and outpatients.
• Training medical detection dogs using reward-based reinforcement to differentiate between SARS-CoV-2-positive and negative samples.
• Evaluating dog performance in both a laboratory testing phase and a real-world hospital screening setting.

Main Results:

• Dogs demonstrated high accuracy in detecting SARS-CoV-2, with an overall diagnostic sensitivity of 98% and specificity of 92% in the testing phase.
• In a follow-up hospital screening, one dog achieved 96% sensitivity and 100% specificity in detecting SARS-CoV-2 among 153 patients.
• The study included a diverse age range (6-97 years) with 24% of samples testing positive for SARS-CoV-2.

Conclusions:

• Canine olfaction presents a highly accurate and feasible approach for diagnosing SARS-CoV-2 infections.
• Medical detection dogs can effectively identify individuals with SARS-CoV-2, including those who are asymptomatic or presymptomatic.
• This method offers a promising, noninvasive alternative for widespread COVID-19 screening.