Researchers Determine Dogs Can Sniff Out COVID-19

A new study from the UK found people infected with the virus that causes COVID-19 emit a distinct odor, one that can be detected by specially trained dogs.

The study, which has not been peer-reviewed, was led by the London School of Hygiene and Tropical Medicine in partnership with Durham University and the charity Medical Detection Dogs. In the study, researchers sought to find a "rapid, accurate, non-invasive diagnostic screen" to identify people with SARS-CoV-2, the virus that causes COVID-19. According to their results, trained dogs that could detect the virus with a sensitivity range of 82-94 percent and a specificity range of 76-92 percent — could be the solution.

Over the course of several weeks, six dogs were presented with odor samples from 200 individuals who tested positive for COVID-19, and 200 individuals whose tests were negative. According to the study, "the dogs were rewarded for correctly indicating a positive sample, or for correctly ignoring a negative sample."

Handlers prompted the dogs to explore the samples from behind a one-way screen, so as to not give the dogs any visual cues.

Researchers concluded that these results could easily be adapted for and used in real-world situations outside of the laboratory. "Our recent work shows that dogs trained in the study readily transition from laboratory-sample testing to identifying people wearing shirts worn by people with SARS-CoV-2 (unpublished)," said the study. "This work is encouraging and suggests that trained dogs will readily identify people infected with SARS-CoV-2 from lines of uninfected people."

The study's researchers also predict that dogs will continue to improve in both specificity and sensitivity in the real world, with those positive with SARS-CoV-2 providing a "larger and clearer" odor profile compared to what was used in the lab.

"These fantastic results are further evidence that dogs are one of the most reliable biosensors for detecting the odor of human disease. Our robust study shows the huge potential for dogs to help in the fight against COVID-19," Dr. Claire Guest, the chief scientific officer at Medical Detection Dogs, said in a release. "Knowing that we can harness the amazing power of a dog's nose to detect COVID-19 quickly and non-invasively gives us hope for a return to a more normal way of life through safer travel and access to public places, so that we can again socialize with family and friends."