Dogs are being trained to sniff out COVID-19 at the airport

Airport dogs are being trained to detect people infected with COVID-19. (Photo: Getty Images)
Airport dogs are being trained to detect people infected with COVID-19. (Photo: Getty Images)

Finland’s Helsinki Airport is using a unique method for screening arriving passengers for COVID-19: specially-trained dogs that can detect the virus in humans — even before they show any symptoms.

It’s part of a new pilot program, which started this week, designed to find “new and efficient ways” to reduce the spread of the coronavirus, according to a press release issued by Helsinki Airport.

Dubai International Airport was the first to use coronavirus-sniffing dogs when it launched a program this past summer. Other countries, including the U.S., Australia, Germany and France, are also looking into using medical detection dogs, according to the Associated Press.

In Finland, four dogs (including a Greyhound mix) — trained to detect the virus in passengers mainly arriving from outside the country — are already working at the airport in shifts, with more dogs currently being trained. (Yahoo Life reached out to Wise Nose - Finland Smell Detection Association, who partnered with the University of Helsinki’s veterinary faculty to train the dogs for the Helsinki Airport, but did not receive a response.)

Upon arrival at the airport, passengers may be asked to volunteer for the program, and if they agree, are given a wipe to collect a sweat sample. There’s no direct contact between passengers and the dogs. According to the press release: “The dog will perform its work in a separate booth. Those taking the test will swipe their skin with a test wipe and drop it into a cup, which is then given to the dog. This also protects the dog’s handler from infections. All the tests are processed anonymously.”

The trained dogs can pick up the scent of a COVID-19 patient in a mere 10 seconds, according to the New York Times — and long before patients themselves even know they’re sick.

“What we’ve seen in our research is that the dogs will find [the coronavirus] five days before [patients] get any clinical symptoms,” Anna Hielm-Bjorkman, an adjunct professor specializing in clinical research for companion animals at the University of Helsinki, told Reuters.

If the medical detection dog signals that a person is infected, the passenger is then asked to take a nasal swab test for the coronavirus to confirm the dog’s findings.

Dogs’ amazing sense of smell

Researchers are still trying to understand the relationship between illness and scent, but it appears that the sweat, breath and urine of people infected with certain diseases give off a telltale odor, according to National Geographic. “We believe all diseases have scent associated with [them], due to the changes occurring within the body, with different organs expressing different chemical compounds,” Ralph Hendrix, director of finance and former executive director of Dogs4Diabetics, which trains medical alert service dogs, including in scent detection, told Medical News Today. “These scents are evident in breath and sweat.”

Dogs are naturally adept at picking up scents, making them ideal disease detectors. They can “sniff in parts per trillion, as well as in 3-D,” Maria Goodavage, author of Doctor Dogs: How Our Best Friends are Becoming Our Best Medicine, tells Yahoo Life. “Dogs have much better olfactory anatomy than we do. We have about 6 million olfactory receptors and dogs have up to 300 million. Their brains are better equipped to make sense of scents. Their olfactory world is rich and vivid, much like our visual world.”

While we’re still in the early stages of discovering what dog noses are capable of — “We recently learned that their nostrils can sniff independently of each other,” Goodavage says — experts say they can be trained to detect COVID-19, as well as other health conditions, including cancer, malaria, and potentially seizures.

Researchers train dogs to sniff out the coronavirus in a variety of ways, including by using “chemically-deactivated urine,” Goodavage tells Yahoo Life. “Some use nasopharyngeal swabs. Some use underarm swabs for sweat. Others use saliva [and] some use sebum. The University of Pennsylvania’s Penn Vet Working Dog Center has been collecting t-shirts worn by people with and without positive COVID tests.”

A July 2020 pilot study published in the journal BMC Infectious Diseases, noted that “volatile organic compounds produced during respiratory infections can cause specific scent imprints, which can be detected by trained dogs with a high rate of precision.”

In the study, eight dogs were trained for one week to detect saliva or tracheobronchial secretions from patients infected with COVID-19. The dogs’ overall success rate for determining which samples were from infected patients and which ones were uninfected samples was 94 percent.

But dogs’ “astonishingly good noses” aren’t the only reason they’re so skilled at detecting odors. “Their bonds with the people in their lives are also key,” says Goodavage. “When working in studies… dogs work for the ‘paycheck’ of treats or toys, and heartfelt praise. When they live with and work beside people whose illness they’re trained to detect and alert to, though, their work goes beyond being reward-driven. The dogs I’ve seen really appear to know that what they’re doing is incredibly important.”

Goodavage adds that “highly trained dogs have recently become invaluable allies on the frontlines of medicine,” and they may one day help pave the way for better disease detection tools for people.

Researchers are “working hard to find out just what it is the dogs are sniffing” in infected patients, says Goodavage. “If researchers can find out, they’re hoping to be able to create ‘electronic noses’ to detect cancers in their earliest stages, and do so noninvasively, accurately, rapidly, and at a low cost.”

Dogs, who have been faithful companions to humans going as far back as 40,000 years ago, “may lead to this exciting new technology,” says Goodavage, “and what a great accomplishment that would be.”

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