COVID pawsitive: A pilot study successfully used dogs to sniff out COVID-19 in schoolchildren

Not only did dogs excel at screening for COVID-19, but researchers saved on medical waste from antigen tests too

By Nicole Karlis

Senior Writer

Published April 25, 2023 2:59PM (EDT)

Anti-Covid dogs in the room where they smell the swabs trained by professionals in the fields of safety & security to recognise the presence of Covid-19 in the sweat of patients at the Drive-in Campus test at the Policlinico Universitario Campus Bio-Medico, on March 29, 2021 in Rome, Italy. (Simona Granati - Corbis/Corbis via Getty Images)
Anti-Covid dogs in the room where they smell the swabs trained by professionals in the fields of safety & security to recognise the presence of Covid-19 in the sweat of patients at the Drive-in Campus test at the Policlinico Universitario Campus Bio-Medico, on March 29, 2021 in Rome, Italy. (Simona Granati - Corbis/Corbis via Getty Images)

Nobody likes having an oversized nasal swab shoved up their nose for a COVID-19 test  — especially kids.

Even as COVID-19 precautions fade in other sectors of society, K-12 schools are one realm where masking and testing is common. For some children, that means enduring uncomfortable nasal swabs multiple times a month. 

But what if instead of regular antigen COVID-19 testing, children in schools were initially screened by dogs?

It's a wholesome idea that is actually a reality in some schools in California, where a pilot program was performed. According to a study published Monday in the journal JAMA Pediatrics, the pilot program was such a success that they recommend this strategy to be adopted in schools across the country — and possibly to be used to detect other diseases, too.

"While modifications are needed before widespread implementation, this study supports use of dogs for efficient and noninvasive COVID-19 screening and could be used for other pathogens," the researchers stated.

In the paper, the researchers explained that their goal was to use dogs to screen for possible COVID-19 cases, and to only use antigen tests on kids whom the dogs screened as positive. The idea came to Dr. Carol A. Glaser, who works for the California Department of Public Health, when she and her colleagues kept bumping up against all the barriers schools faced to do routine COVID-19 antigen testing.

"It took a lot of personnel time to be able to do those tests because we often relied on teachers or their administrative staff to do it," Glaser told Salon. "It would take the children out of school time, and there was a lot of biomedical waste that was generated."

"So we began to think, 'wouldn't this be great if the dogs could do the initial screening of the students and the staff?'"

Meanwhile, they heard about how dogs could potentially detect COVID-19 in people. Indeed, when a person is infected with the COVID-19, or any disease, it causes metabolic changes that result in the production of something called volatile organic compounds (VOCs). VOCs are often associated with man-made chemicals, and are off-gassed from certain drying paints and lacquers. But volatile organic compounds also scent perfumes, and they are emitted by animals and plants as well. Certain VOCs are expelled from a person's breath and sweat when they have COVID-19, and dogs can be trained to detect such scents.

"So we began to think, 'wouldn't this be great if the dogs could do the initial screening of the students and the staff?'" Glaser said. "And then you'd always want to back that up with a test such as an antigen or a PCR test."

Unlike humans, dogs perceive the world primarily through their hyper-sensitive noses, which are estimated to be between 1,000 and 10,000 times more sensitive than ours, depending on the breed. While dogs like bloodhounds have long been used to track scents, only more recently have dogs been tested in a medical setting. In the early days of the pandemic, there were proposals to train dogs to do the same for COVID-19, and in 2021 dogs at the Miami airport were trained to do just that. 

This most recent pilot program in schools was also effective at reducing medical waste. According to the study authors, the pilot program reduced the volume of antigen tests performed by about 85 percent.

The dogs used in the pilot program were two yellow Labradors named Rizzo and Scarlett. Between April and May of 2022, they visited 27 schools in California to screen for COVID-19; in total, they completed more than 3,800 screening tests.


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An in-person screening worked like this: students lined up six feet apart, and the dogs — led by handlers — sniffed the children's ankles and feet. If the dogs detected a possible COVID-19 infection, they'd alert their handlers by sitting. When this happened, the children would then proceed to undergo a BinaxNOW (Abbott) antigen testing.

Within two months, the dogs' success rate impressed the researchers, as they accurately ruled out 3,411 infections. However, according to the study, they inaccurately signaled an infection in 383 cases and missed 18 infections.

Still, the program was so successful that Glaser and her colleagues are now doing another program as well as piloting dogs to detect COVID-19 in nursing homes.

As Salon has previously reported, dogs can be trained to detect when a person with diabetes is experiencing low or high blood sugar, or when someone with a seizure disorder is going to have a seizure. They are able to sniff out several types of cancer in samples of blood, urine, sweat, saliva, and exhaled breaths.

"We do know from a lot of studies that there's unique volatile organic compounds released by individuals that have influenza, so we'd like to be able to train them on influenza you know, at some point," Glaser said. "And we also know that nursing homes, just like other places, have really explosive outbreaks with influenza, so we think that that would be a really good fit."


By Nicole Karlis

Nicole Karlis is a senior writer at Salon, specializing in health and science. Tweet her @nicolekarlis.

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