Helsinki Airport Employs Dogs to Sniff Out Signs of Covid-19 in Travelers’ Sweat

Four dogs began work at Helsinki Airport on September 22, and six more may join them soon

The coronavirus sniffer dogs named Kössi (L) and Miina cuddle with trainer Susanna Paavilainen at the Helsinki airport in Vantaa, Finland
Caption via Getty: "The coronavirus sniffer dogs named Kössi (L) and Miina cuddle with trainer Susanna Paavilainen at the Helsinki airport in Vantaa, Finland where they are trained to detect the Covid-19 from the arriving passengers, on September 22, 2020." Photo by ANTTI AIMO-KOIVISTO/Lehtikuva/AFP via Getty Images

On September 22, Finland’s Helsinki Airport welcomed a new team of four-legged employees with a very important job. The four dogs—Kössi, Miina, Valo and E.T.—are experts at sniffing sweaty wipes for signs that a traveler is infected with the virus that causes Covid-19.

International arrivals at Helsinki airport are now invited to the dogs’ Covid-19 testing area. Each passenger is invited into a private room where they use a wipe to dab their travel-sweaty selves, and then drop the wipe in a metal cannister. The dog’s trainer puts the can in a lineup with four others, and then the dog can go to work sniffing all five cans.

If the dog makes a signal, like tapping the ground at the traveler’s sample, the dog gets a treat.

The traveler gets directed to the airline’s health center, where they receive a Covid-19 lab test for free, Elian Peltier reports for the New York Times.

During preliminary tests at the University of Helsinki, dogs were able to detect the coronavirus in a sample with almost 100 percent certainty, according to a statement by the company that manages the Helsinki airport. The university found that dogs can also identify a Covid-19 case days before a person began showing symptoms.

People can spread the virus before they show symptoms, but might not think to take a lab test until they do. The airport’s disease-sensing dogs help ensure that international arrivals are screened thoroughly.

“We know how dogs detect it — by smell — but we have no clue what they detect yet,” Anna Hielm-Bjorkman, an professor at the University of Helsinki who is leading the trial, tells the New York Times. “If we find this out, we can train thousands of dogs across the world.”

Dogs have long been trained to sniff out diseases like malaria, diabetes, cancers and Parkinson’s disease, and this spring trials began around the world to train dogs on Covid-19’s scent, Alex Fox reported for Smithsonian magazine in May. A French study published in June found “very high evidence” that sweat from Covid-positive people contains a scent that dogs could discern, Jon Henley reports for the Guardian.

One of the Helsinki airport dogs, Kössi, has years of experience searching for signs of disease in medical samples, per YLE in July. The eight-year-old greyhound mix learned to identify samples from Covid-19 patients in just seven minutes, according to the airport’s statement.

The dogs’ sample-sniffing process takes just ten seconds, and the entire test takes about a minute.

“It’s very promising,” Hielm-Björkman tells the Guardian. “If it works, it could prove a good screening method in other places” like hospitals, care homes, and at events that draw large crowds like professional sports. Hielm-Björkman told YLE in July that embassies, customs agencies and police dog trainers also expressed an interest in the dogs’ talents.

Helsinki airport is the second airport to employ dogs to search for the coronavirus. Dubai deployed police dogs trained to find Covid-19 cases in airports this summer, Hayley Skirka reported for the National in July.

“All dogs can be trained to smell the coronavirus, but they are individuals and not all of them can work in an airport,” Virpi Perala, a representative of the Evidensia network of hospitals and veterinary clinics, which funded the first stage of the Helsinki trial, tells the New York Times.

Finland would need to train between 700 and 1,000 dogs in order to cover crowded places like schools, malls and retirement homes, Perala tells the New York Times. This first four-month trial cost about $350,000, which is significantly cheaper than conducting lab-based tests on every international visitor, city authorities tell the Guardian.

The pilot may show how effective dogs are at slowing or stopping the introduction of new Covid-19 into the country. The researchers also noticed in July that the dogs would “identify someone as sick long after their recovery” from the virus, Hielm-Björkman told YLE.

The four Covid-19-sniffing dogs at the Helsinki airport were trained by Wise Nose, which is now training a dozen more. Six of them aren’t suited to the bustling environment of an airport, so soon there will be ten dogs total working at the airport’s Covid-19 testing station.

For now, the four dogs on duty work in two shifts—two dogs are at work at a time, while the other two (and their trainers) rest.

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