Dogs are host to a slew of amazing capabilities which include a range of superior senses compared to humans. Using their amazing sense of smell, dog trainers have been able to create medical alert dogs, able to not only diagnose disease but also to alert humans to changing medical conditions. With amazing success, dogs can alert to various cancers, seizure disorders, diabetes, and even detect if a migraine will develop. Using the same proven methods, researchers are experimenting with the possibility of using dogs to help alert to COVID-19 in patients, which could lead to a faster and more accurate screening process.
Success Detecting Cancer
Compared to humans, dogs have some pretty incredible senses. Not only can dogs hear and see better than humans, but they can smell better too. This is due to their increased scent glands allowing certain breeds of dogs to smell between 10,000 and 100,000 times better than a human. Plus, a dog's nose is incredibly sensitive, able to differentiate between scents picked up from the left or right nostril. With over 300 short breaths per minute, a dog is constantly getting a wave of fresh scents to process, allowing a dog to have a superior olfactory system. While historically this amazing sense of smell has been put to use for hunting, researchers and dog trainers alike are using dogs to help detect the presence of certain diseases.
Although it may seem far fetched that dogs might be able to detect COVID-19 in people, there is a precedent established for using a dog's ability to smell for disease detection. It turns out that certain diseases, like cancer, have a very specific smell, which even humans are able to detect in the later stages of the disease. Due to their incredible sense of smell dogs can detect the presence of cancer in the human body, even before it begins to spread. Training a dog to detect cancer in humans usually takes about 8 months and consists of dogs smelling cancer cells in various forms, including human plasma, urine, and saliva. Dogs are trained on about 300 different samples until they are able to successfully identify cancer in humans.
With a team of trained dogs it was possible to positively detect breast cancer with about 88% accuracy, and detect lung cancer with about 99% accuracy. This success rate is true for cancers in all four stages, taken from a range of samples from different humans. In fact, dogs were even able to successfully indicate that a person had cancer from smelling blood samples 97% of the time. Recent studies have proven that dogs are able to detect cancer in humans, keying in on indicators that even modern medical tests cannot identify yet. It is entirely within the realm of possibilities that trainers and researchers can put these same practices to use when trying to detect the early signs of COVID-19.
A dog's incredible medical capacity doesn't end at simply being able to detect the presence of a disease. It turns out that many diseases have a smell associated with dangerous changes and complications that dogs can also detect. Consider dogs that are trained to help identify and alert to a pending narcolepsy attack. Before the body begins an attack the body creates certain chemicals. These specific chemicals have a smell that dogs are able to hone in on, usually about five minutes before the chemical takes effect on the body. Through proper training, a dog is able to alert a human that an attack is coming so that a human can properly prepare.
Plus, dogs are able to help with a range of other diseases too. Dogs are able to help identify an incoming seizure or even a pending migraine all by recognizing and alerting their human to changes in smells associated with the medical condition. In fact, dogs can be a virtual life saver for people suffering from diabetes. When blood sugar drops dangerously low the body releases a chemical called isoprene. Not only are dogs able to smell this chemical and alert their human, but they are able to differentiate between existing isoprene and newly formed isoprene in the body. Dogs can recognize changes in behavior when a migraine is about two hours away from fully forming, or help alert humans about an incoming psychological or physical seizure. Dogs have also been used to help diagnose Parkinson's disease and malaria in children as well.
New Advances With COVID-19
To fight against the global pandemic researchers are examining ways in which dogs may be able to help detect the presence of COVID-19 in humans. Research is already underway at both the London School of Hygiene and Tropical Medicine and The University of Pennsylvania to study the possibility of early canine detection for this disease. A team of Labrador retrievers is being used to help test this theory.
It is uncertain whether COVID-19 itself has a recognizable smell, similar to cancer, or if the dogs will be able to pick up on the body's response to the presence of the disease, similar to the way a dog will alert to low blood sugar or a narcolepsy attack. Testing is still underway to help dogs both identify the scent as well as help alert and indicate once the scent has been acquired. The long term outlook for this project is to create a team of highly accurate, and highly trained canines to help screen humans for this potentially life threatening disease. If used at an airport, this screening method would be able to screen up to 250 airline passengers per hour, much faster than conventional testing methods. Although the results of their independent studies have not been published yet, the prospect and viability of a COVID-19 alert dog seem promising.