A new study from the University of Pennsylvania has demonstrated that dogs can sniff out coronavirus with remarkable accuracy. Specially trained detection dogs were found to correctly identify COVID-positive urine and saliva samples 96 percent of the time.
Study senior author Cynthia Otto is the director of the Penn Vet Working Dog Center in the School of Veterinary Medicine.
“This is not a simple thing we’re asking the dogs to do,” said Otto. “Dogs have to be specific about detecting the odor of the infection, but they also have to generalize across the background odors of different people: men and women, adults and children, people of different ethnicities and geographies.”
While dogs are capable of doing this, the researchers found that training for coronavirus detection must proceed with great consideration and with many samples.
“Future training of dogs and investigation into biological, chemical and electronic detectors should focus on increasing the number of relevant and novel samples,” noted the researchers.
The findings from this study are being used for another investigation by the team. In “the T-shirt study,” dogs are trained to distinguish between the odors of COVID-positive, -negative, and -vaccinated individuals based on volatile organic compounds left behind on a T-shirt worn overnight.
“We are collecting many more samples in that study – hundreds or more – than we did in this first one, and are hopeful that will get the dogs closer to what they might encounter in a community setting,” said Otto, who has had years of experience training medical-detection dogs, including those that can identify ovarian cancer.
For the current study, eight Labrador retrievers and a Belgian Malinois were used that had not done medical-detection work before.
After three weeks of training all nine dogs could identify SARS-CoV-2 positive samples with an average of 96 percent accuracy. The ability of the dogs to avoid false negatives, however, was not as reliable. The researchers believe this may have been simply due to the strict criteria of the study.
Beyond confirming that dogs can detect a specific SARS-CoV-2 odor, the experts identified mistakes that can be avoided in the future. For example, they found that training should entail large numbers of diverse samples and that dogs should not be trained repeatedly on the samples from any single individual.
“That’s something we can carry forward not only in our COVID training but in our cancer work and any other medical detection efforts we do,” said Otto. “We want to make sure that we have all the steps in place to ensure quality, reproducibility, validity, and safety for when we operationalize our dogs and have them start screening in community settings.”
The study is published in the journal PLOS ONE.