Can Dogs Detect COVID-19?
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A dog's sense of smell is impeccable. Their olfactory ability has led them to be employed as working animals in various roles. Many people are aware of drug sniffing dogs, tracking dogs and even water rescue dogs. Some may not be so familiar with a dog's use as medical detection dogs. Since the field is in its relative infancy, it may be understandable why you have not heard of dogs being used in this capacity. However, due to their acute sense of smell, practitioners have found evidence it is possible for dogs to detect certain diseases such as cancer.
However, when outbreaks such as the coronavirus pandemic rely on track and trace methods of containment, knowing can dogs detect COVID-19 might be a huge step forward in relief efforts. AnimalWised looks into whether dogs can smell coronavirus to see what might happen in the future.
A dog's sense of smell
The olfactory sensitivity of dogs is much more acute than that of humans. This has been shown in various studies looking into the sense capacity of dogs. Sense of smell is a canine's most advanced sense, although a dog's eyesight is not as limited as some believe it to be. For example, a dog can see some colors, but not as many as we can.
One interesting experiment demonstrated the olfactory ability of dogs with twins. The dogs in the study could detect between fraternal twins, but not between identical twins because of the latter having the same DNA.
Thanks to this amazing ability, dogs can perform a wide array of smelling tasks. These include:
- Locating wild truffles
- Hunting game and other prey
- Drug detection
- Bomb detection
- Mountain and sea rescue
What is not as well known is the fact that dogs can detect certain diseases in a human being. It is important to point out there are many different factors and issues regarding this practice. For example, it is possible a dog may only be able to detect a disease once it is at a certain stage.
Although there are some breeds which are considered to have special ability when it comes to smell, such as game hounds, all healthy dogs will have an acute ability. This is because their nose has more than 200 million odor receptor cells. In comparison, humans only have about 5 million. Furthermore, the olfactory center of a dog's brain is highly developed and the nasal cavity is profusely innervated (i.e. full of nerves). A large portion of their brain is dedicated to detecting smell. It is better than any artificial smell sensor created by humans. For all of these reasons, it may not surprise you to know that some academics have been researching whether it is possible for a dog to detect the novel coronavirus (COVID-19).
How do dogs detect disease?
A dog's sense of smell is so acute that it allows them to detect diseases in people. Of course, this requires prior training. A dog will not simply alert a human to the presence of disease. They need to be trained to do so, but fundamentally their innate olfactory ability is being harnessed. As advances in medicine have been achieved, it has been shown that dogs can detect pathologies in humans including:
- Prostate cancer
- Intestinal cancer
- Ovarian cancer
- Colon cancer
- Lung cancer
- Breast cancer
- Diabetes
- Malaria
- Parkinson's disease
- Epilepsy
Dogs achieve this feat by detecting specific volatile organic chemicals (VOCs) which are produced by certain disease. In other words, each disease has it's own characteristic scent which the dog is capable of discovering. It may even be possible for a dog to detect diseases at stages which are so early, other medical tests art not able to do so. The efficacy of such detection is very high. For example, a dog is able to detect changes in glucose levels up to 20 minutes before there is a detectable change in their blood.
Early detection is essential in improving the prognosis of diseases such as cancer. Similarly, anticipating rises in blood glucose levels for diabetics or detecting the onset of epileptic seizures. This can signal a huge improvement in the quality of life of those affected by certain medical conditions. Additionally, it assists researchers in identifying biomarkers to help improve other diagnostic systems.
The basic concept is that dogs are taught to look for the specific chemical compound (the VOC) characteristic of a given disease. To do so, they are presented with samples of feces, saliva, blood or even tissue to recognize the odors. They can then alert technicians when they perceive the same scent in a patient. They can even be taught to sit down or stand whether or not the odor is present.
When the dog is working with a patient, they can alert to the presence of a VOC by touching them with a paw. Training in this discipline lasts several months and is intensive. It must only be carried out by professionals. In lieu of this information, it is not surprising researchers into COVID-19 detection are considering it as a possible option.
Can dogs detect coronavirus?
After years of research into detecting diseases, it is not surprising to know that the science suggests dogs can detect coronavirus. While conclusive results have yet to be confirmed, preliminary tests point towards a positive assessment. One such test at the University of Helsinki has shown positive results in differentiating between the urine of COVID-19 patients and those who do not have it[1]. The same researchers suggest the dogs are able to detect the disease quicker and with more sensitivity than other proposed tests.
Positive tests with the DogRisk project
The group in control of the research is known as DogRisk and they are the ones who have been able to identify the urine samples. They are currently in the phase of collecting more samples to train more dogs. After this time, they can hopefully determine how long the VOC remains after the infection has ended. Additionally, they have been checking the dog's sensitivity by providing samples which do not have coronavirus, but which have similar respiratory diseases.
Super Six dogs: training in process
In the UK, there is a canine team which is being trained for the detection of COVID-19. The team consists of six dogs and have been named the Super Six. Three dogs are Cocker Spaniels (named Norman, Jasper and Asher), there is a Labrador Retriever named Star, a Golden Retriever mix named Storm and a Labradoodle called Digby. All the dogs are between 20 months and 5 years of age.
The objective of the Super Six is to detect the odor of the virus in less than a second with both symptomatic and non-symptomatic patients. If successful, rapid and non-invasive diagnoses can be carried out. Samples have been collected from both the breath and sweat of affected persons. The Medical Detection Dogs organization is leading the project in conjunction with Durham University. They hope to finish the training in 6 to 8 weeks so they can start working directly with people. The hope is they will be able to smell the air around them to determine a diagnosis.
In addition to these teams, dogs are also being groomed in the United States. At the University of Pennsylvania School of Veterinary Medicine they are working with a team of eight dogs. They are expected to be ready in a matter of weeks. Additionally, various organizations in Spain and other parts of the world are also considering the option of training dogs to detect COVID-19.
Coronavirus and animals
Now that you know that dogs can detect coronaviruses, like other diseases, you may also be interested in reading some of these other articles related to COVID-19:
- Taking care of your dog during quarantine
- How to clean a dog's paws after a walk during quarantine
- Canine coronavirus
Below we also share some helpful videos for animal guardians during this time of pandemic:
If you want to read similar articles to Can Dogs Detect COVID-19?, we recommend you visit our Facts about the animal kingdom category.
1. University of Helsinki/Miia Soininen. (2020). The Finnish COVID dogs’ nose knows!
https://www.helsinki.fi/en/news/health-news/the-finnish-covid-dogs-nose-knows
- Carlson J. M.,& Giffin, D. G.. (2002). Practical Canine Veterinary Manual. Madrid: Editorial El Drac.
- Fogle, B. (1995). The Encyclopedia of the Dog. London: Dorling Kindersley.
- Morris, D. (1988). Observe your dog. Barcelona: Janés Square.
- Veterinary Portal. (2020). Dogs trained to detect the coronavirus.
