By Jed Weisberger
Would you be uncomfortable with a trained working dog assisting your oncologist or diabetes specialist in making a diagnosis?
Such canine assistants just might be making an appearance in the future as an additional confirmation of a human malady in need of treatment. Many studies around the world are showing trained dogs have that ability.
“Never deny the power of a dog’s nose,” said Director, Penn Vet Working Dog Center, University of Pennsylvania School of Veterinary Medicine during an address to IWDC. 2021 last October, explaining a dog processes daily experiences as a human does visually.
“We train our dogs to be ‘odor discriminate,’ ” said Otto. “Different diseases emit different odors to a canine. A woman with ovarian cancer has a different owner than a healthy woman. We want our dogs to recognize different odors.”
Dogs have also been able to detect Covid in patients. A 2021 University of Pennsylvania study which involved Otto and coronavirus expert Susan Weiss of Penn Medicine, utilized T-shirts study subjects wore overnight. Trained dogs were able to detect positive Covid samples from a deactivated virus at a 96% rate.
Also, IWDBA Board Member Dr. Esther Schalke, who has worked with the German Armed Forces School for Service Dogs since 2019, had a group that conducted a study proving dogs can detect Covid in October 2021,
In Schalke’s group, a pilot study with 10 dogs were trained to detect SARS-CoV-2 infections in beta-propiolactone inactivated saliva samples. They were able to discriminate between samples from infected patients and negative controls. The cognitive transfer performance for the recognition of non-inactivated sample material and detection accuracy were tested on three different non-inactivated body fluids (saliva, urine, sweat) in a random double-blind controlled study.
Dogs were tested on a total of 5,242 random samples. They detected non-inactivated saliva samples with an average sensitivity of 84% (95% CI: 62·5–94·44%) and specificity of 95% (95% CI: 93·4–96·0%). In a subsequent experiment to compare the scent recognition between the three non-inactivated body fluids, diagnostic sensitivity and specificity were 95% (95% CI: 66·67–100%) and 98% (95% CI: 94·87–100%) for urine, 91% (95% CI: 71·43–100%) and 94% (95% CI: 90·91–97·78%) for sweat, 82% (95% CI: 64·29–95·24%), and 96% (95% CI: 94·95–98·9% ) for saliva respectively.
In conclusion, detection dogs were able to transfer the conditioned scent detection of inactivated saliva samples to non-inactivated saliva, urine and sweat samples, with a sensitivity more than 80% and specificity of more than 94%. All three fluids were equally suited for SARS-CoV-2 detection by dogs and could be used for disease-specific recognition. This shows detection dogs may provide a reliable screening method for SARS-CoV-2 infections.
The above numbers, in addition to other studies, have proven dogs can detect several forms of cancer due to a unique “cancer odor” developing tumors emit. Additional studies have shown trained working dogs can detect blood sugar levels. All this is due to the ability of the canine olfactory.
A clinical future for these dogs is a possibility.