In fact, many animal species have proven their ability to detect diseases ranging from cancer to urinary tract infections, Covid-19 and the gastrointestinal infection Clostridium difficile. Many of these diseases are potentially serious, especially in vulnerable and immunocompromised patients. Accurate and early detection is therefore essential.
Sniffing out health problems
How are these animals able to identify the presence of specific diseases? Jacqueline Boyd, a lecturer in animal sciences at Nottingham Trent University in England, explains in an article for The Conversation that many species are able to detect tiny changes in a person’s chemical olfactory profile.
The human body releases very small amounts of substances called volatile organic compounds. The composition and concentration of the compounds changes depending on a person’s health status and will be different if they are fighting an infection or dealing with a health problem.
The skills that different species have for accurately detecting diseases could make trained detection animals an effective, non-invasive, fast and cost-effective way to screen for specific health problems. Here are the best ones to help us out:
Dogs
Parkinson’s disease, bladder cancer , malaria, epileptic seizures, hypoglycemia in diabetic patients… nothing escapes our four-legged friends. When they are trained to detect certain diseases, nothing stops them.
Their sense of smell is exceptional: it is said to be 10,000 times better than ours. They can even use their nostrils independently of each other to search for new smells. By training them to associate specific smells with a positive reward, they are able to recognize physical and behavioral changes and predict crises or health problems.
Rats
Rats are also good at detecting specific odors. For example, the African giant pouched rat can recognize the smell of landmine explosives in Mozambique. In the medical field, they have proven themselves by detecting cases of tuberculosis in sputum samples collected from suspected cases. Very fast, they take only 20 minutes to examine 100 samples and accurately detect positive samples 81% of the time.
Their reward for a job well done is an avocado and banana treat, Boyd says. That makes these trained rats a valuable option when time and money may be limited at diagnostic and screening facilities.
Also Read: 3 animals capable of detecting diseases in humans
The bees
Extremely sensitive to odors at low concentrations, bees can detect signs of certain diseases in samples, including lung cancer , tuberculosis and COVID-19.
The researchers successfully trained bees to respond to the presence of specific odors to obtain a sweet reward. With training, this response becomes consistent and highly sensitive to odors linked to disease states. Their size could make them an even more efficient and inexpensive option for rapid screening of samples.
