Pet Connection by Dr. Marty Becker, Kim Campbell Thornton and Mikkel Becker

Scent Sense

Dogs put their noses to work to learn how to identify and detect the COVID-19 virus

By Kim Campbell Thornton

Andrews McMeel Syndication

If there’s anything most people know about dogs, it’s that they have an incredible sense of smell. We’ve put their sensitive noses -- which have up to 300 million scent receptors compared to our measly 6 million or so -- to work sniffing out drugs, explosives, truffles, cancer, turtle eggs, jaguar scat and contraband fruits, plants and meats. Now they’re busy learning a new odor: the COVID-19 virus. Researchers around the world are working with dogs to find the best ways for them to aid testing and diagnosis.

In France, scientists have volunteers working up a sweat. Body fluids such as urine, tears, saliva and perspiration contain volatile organic compounds that contribute to body odor. At Ecole Nationale Veterinaire in Alfort, as well as the University of Corsica and the French-Lebanese University of Beirut, researchers gathered samples of armpit sweat and trained 18 dogs, mostly Belgian Malinois, to see if they could sniff out a difference in the sweat of patients who tested positive for the virus and those who didn’t.

“We did not know if there was any specific odor to the virus,” says Dominique Grandjean, DMV, Ph.D., a professor at ENV and lead author of the as-yet-unpublished study detailing the findings. “Now we know that there is one.” He explained that dogs smell catabolites related to the action or replication of the virus that escape the body through the sweat.

Interestingly, every dog alerted on two samples from patients who were negative for the virus. A week later, those patients had come down with the disease. If those types of alerts are replicated, it may be that the dogs could serve as an early warning system.

Training dogs to detect the virus is more difficult than training them to detect cancers. For the virus, they had to rely on PCR (polymerase chain reaction) tests, which are not fully reliable, especially if they are negative, Dr. Grandjean says. “We need to train the dogs on both positive and negative samples.”

Veterinary and human medicine researchers at the University of Helsinki in Finland have trained dogs to differentiate the urine samples of COVID-19 patients from those of healthy people. Their goal now is to identify the specific substance the dogs are smelling in the urine of patients, determine how long the odor lasts after recovery, and retest the dogs’ abilities in a randomized double-blind setting with a larger number of patient samples.

The University of Pennsylvania School of Veterinary Medicine, already known for training medical scent detection dogs, began a pilot training program in April to teach eight dogs to discriminate between samples of urine or saliva from patients who were positive for COVID-19 and individuals who tested negative for the virus. Currently, the study has been paused because of a delay in COVID sample collection, says communications coordinator John M. Donges in an email. But once the dogs learn the odor and their ability has been documented in a laboratory setting, it’s hoped that their olfactory abilities could help to reduce community spread of the disease.

That could happen several ways. Disease-control experts at the London School of Hygiene & Tropical Medicine, working with Medical Detection Dogs and Durham University, are looking at whether dogs can learn to detect the odor of coronavirus even in people who don’t show symptoms. If so, trained dogs could be deployed at airports and other entry points in the United Kingdom, helping to screen up to 250 people per hour quickly and noninvasively. Trained dogs could also screen people at sports events or other large gatherings, or in schools, nursing or retirement homes, or hospitals.


Signs of IBD

not always clear

Q: My vet thinks my cat has inflammatory bowel disease. Why doesn’t she know for sure, and what can you tell me about it?

A: IBD, as it’s known for short, is one of those diseases that’s difficult to diagnose, because the signs -- vomiting, diarrhea, changes in appetite, weight loss, drinking more water and urinating more frequently -- are commonly seen in other diseases as well. And those signs may come and go for no apparent reason.

There’s not a simple test your vet can give and say “Yes, your cat definitely has IBD.” It’s more of a process of elimination -- ruling out all the other possibilities. That can involve testing for parasites and foreign bodies, changing the diet to see if the cat has food allergies or intolerances, checking fecal samples for bacterial infections, ultrasound to look for thickening of intestinal walls or enlarged lymph nodes, and bloodwork and biopsies.

The goal of treatment is to reduce the inflammation causing your cat’s discomfort, restock the gut with healthy “bugs,” and possibly to suppress an overactive immune system. Depending on the signs, that might mean changing the food to something highly digestible and low in fat; adding certain vitamins, prebiotics, probiotics or other supplements; prescribing a broad-spectrum antibiotic; or giving a course of corticosteroids to help calm the immune system and reduce inflammation. Corticosteroids can predispose cats to developing insulin resistance or diabetes, so careful monitoring is important.

Once the diagnosis is made and treatment begins, your cat may have a good prognosis. A lot depends on how far along the disease is by the time it’s diagnosed, how compliant the cat is about receiving medication and how well the body responds to treatment. Be sure to ask your veterinarian about possible side effects to watch for. -- Dr. Marty Becker

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The dogs most at

risk for heatstroke

-- Dogs at greatest risk of heatstroke are seniors, overweight dogs or those with smushed faces. A study of more than 900,000 dogs, published last month in Scientific Reports, found that chow chows, bulldogs, French bulldogs and pugs, as well as dogs 12 or older, were more likely to experience heat-related illness. Dogs with flat faces have constricted upper airways, so it’s more difficult for them to cool themselves by panting. Dogs who are people-pleasers -- think golden retrievers and English springer spaniels -- may overheat because they work too hard and too long without stopping. Senior dogs may have heart or lung conditions that make them vulnerable to heatstroke. Watch for excessive panting, glassy eyes, skin that’s hot to the touch and loss of coordination, and take steps to cool your dog immediately if you see them. Get your dog to the veterinarian ASAP if she collapses or has trouble breathing.

-- Should you -- can you -- clicker-train your ferret, bunny, chicken, guinea pig or other pocket pet? Yes, and yes! Benefits include building confidence, having a pet who comes when called (especially great when your hamster has disappeared into the sofa cushions), fun interactions for both of you, building a stronger bond between you and easier handling at the vet clinic. Before you begin, know your species. Bunnies and hamsters, for instance, may be timid, so go slow and give them time to get used to the new activity.

-- G.I. Joe, a homing pigeon who served in the United States Army Pigeon Service, made a 20-mile flight in 20 minutes, delivering a message that saved the lives of more than 100 troops in World War II. He was presented with the Dickin Medal -- the equivalent for animals of the Victoria Cross or Medal of Honor -- for gallantry. -- Dr. Marty Becker, Kim Campbell Thornton and Mikkel Becker


Pet Connection is produced by a team of pet care experts headed by “The Dr. Oz Show” veterinarian Dr. Marty Becker, founder of the Fear Free organization and author of many best-selling pet care books, and award-winning journalist Kim Campbell Thornton. Joining them is behavior consultant and lead animal trainer for Fear Free Pets Mikkel Becker. Dr. Becker can be found at or on Twitter at DrMartyBecker. Kim Campbell Thornton is at and on Twitter at kkcthornton. Mikkel Becker is at and on Twitter at MikkelBecker.