The sensitive sense of smell that dogs possess has made them popular in various fields such as search and rescue, detection of illegal substances, and even medical diagnoses. Over the years, researchers have been studying the ability of dogs to detect human sickness through smell. The studies conducted so far have found that dogs can detect various diseases in humans through smell. However, before dogs can be properly used in clinical practice, further research and evidence are required.
Dogs and Their Sensitive Sense of Smell
Dogs have a highly developed sense of smell compared to humans. While humans only have about 6 million olfactory receptors in their nose, dogs have over 300 million. Their sense of smell is so sensitive that they can detect even the slightest of odors that humans are unable to sense. When dogs inhale, the air is split into two parts – one part goes to their lungs for breathing while the other part goes to their olfactory system for scent detection. The scent detection part consists of a complex network of nerves, receptors, and brain areas that work together to process the smell.
What Are Dogs Capable of Smelling?
Dogs have a remarkable ability to distinguish between different smells. They can pick up on subtle differences in the scent and differentiate between various smells. This makes them useful in different fields, such as detecting explosives, narcotics, and missing persons. Now, researchers are exploring the potential application of dogs’ ability to detect scents in healthcare. Given their incredible sense, dogs should be capable of detecting chemical changes in the body that humans cannot. These chemical changes may be indicative of certain medical conditions, such as diabetes, seizures, and even cancer.
Can Dogs Smell Sickness in Humans?
Dogs can detect certain medical conditions in humans. Trained dogs can alert their owners of an impending seizure by detecting changes in the body’s odor. Moreover, some dogs are trained to sniff out cancer by detecting the volatile organic compounds (VOCs) that cancer cells emit. However, there is no evidence to suggest conclusively that dogs can detect the flu or a cold in humans. Nevertheless, some studies suggest that dogs can detect certain chemical changes in the body associated with sickness.
Studies That Suggest Dogs Can Smell Diseases in Humans
Cancer
A 2006 study showed that dogs are able to detect cancer from the presented breath samples. In 2019, another study supported this finding by demonstrating that dogs can also detect cancer from blood samples with up to 97% accuracy.
Parasites (Malaria)
A 2019 study found that dogs can detect the odor of sweat from people with malaria. The researchers trained dogs to detect the odor of socks worn by malaria-infected individuals. The dogs were able to distinguish between the socks of infected individuals and those of healthy individuals with an accuracy rate of 70%.
COVID-19
A recent study conducted in 2020 found that dogs can detect COVID-19 in humans with an accuracy rate of up to 94%. The study involved training dogs to distinguish between the odor of sweat samples from COVID-19 patients and healthy individuals. The dogs were able to detect COVID-19 with high accuracy, even in asymptomatic individuals.
Seizures
A study published in 1998 investigated whether dogs could detect the odor of sweat from people with epilepsy and distinguish it from the sweat odor of people who had not had a seizure. The dogs were able to accurately identify the seizure odor with a success rate of 97%. This study provides evidence that dogs can detect changes in the odor of people with epilepsy during seizures and suggests that their exceptional sense of smell may be used as a tool to alert individuals to an impending seizure.
Diabetes
A study published in Diabetes Care in 2013 investigated whether trained dogs could accurately identify the scent of hypoglycemia, or low blood sugar, in people with type 1 diabetes. The study found that trained dogs could accurately detect hypoglycemia by scent alone, and that their alerts were more reliable than current glucose-monitoring technologies. The study suggests that trained dogs could be used as an alternative or complementary tool for detecting hypoglycemia in people with type 1 diabetes.
How Can Dogs Help in Detecting Various Sickness?
Despite the lack of conclusive evidence, dogs can still play a vital role in detecting sickness in humans. Trained dogs can be used to detect various medical conditions, such as diabetes, seizures, and cancer. They can also be used in medical facilities to screen patients for infectious diseases, such as COVID-19. In addition, dogs can help individuals with certain medical conditions by alerting them to an impending medical emergency. For example, dogs can be trained to alert their owners to an oncoming seizure or a drop in blood sugar levels.
Final Thoughts
While the studies completed so far suggest that dogs can detect certain chemical changes associated with sickness, more research is needed to confirm these findings. Nevertheless, the unique sense of smell that dogs possess makes them valuable assets in various fields, including medicine. Their roles could expand in the future as our understanding of their olfactory capabilities continues to grow.
