Can our furry friend sniff out diseases too?  

We adore dogs for different reasons. Apart from being faithful, they also gift us with an immense amount of joy and companionship. Our furry friends are well known for their extraordinary sense of smell too. That’s why they are employed for the detection of hidden drugs, bombs and dead bodies. Do you know that dogs are now used for therapy too? Yes, you read that right. At Roswell Park, a centre that deals with cancer in New York, has many of them to offer emotional support to people. Recent studies show they can also help detect diseases through their keen sense of smell. Let us find out which diseases can be detected by dogs.   

Dogs are born with a strong olfactory sense 
In her study, researcher and author Alexandra Horowitz, based in Columbia University, observes that a dog receives most of its information from its nose. You will be surprised to learn that while a human nose contains about five million scent glands, a dog’s nose has between 125 and 300 million glands! As a result, a dog’s sense of smell is 1,000 to 100,000 times stronger than that of a human.  

According to research, dogs can pick up on trace amounts of scents produced by certain disorders. How little, you may ask. Well, the answer is, around one part per trillion or a single teaspoon of water in two Olympic-sized swimming pools. 

Sniffing out cancer  
Surprised? Well, our four-legged friends are known for their ability to detect cancer. They can be trained to detect a range of cancers, including skin cancer, breast cancer, and bladder cancer. They are trained using samples from cancer patients and healthy people. The capability of dogs to detect melanoma, a potentially lethal skin cancer, has been studied in depth and proven as well, observe experts. In the book Being a Dog, published in 2016, author Alexandra Horowitz writes about a Dachshund puppy that kept sniffing her owner’s armpit. Was she playing with her owner? No, she did not do it for fun! The woman eventually discovered a lump in her armpit, which resulted in a breast cancer diagnosis. 

Dogs and COVID-19 
The coronavirus – SARS-CoV-2 – which caused the COVID-19 pandemic, is the most recent example of dogs detecting sickness. 

In a preliminary study conducted at the University of Helsinki in Finland, scientists trained dogs to identify the previously unknown smell of COVID-19 infection, caused by the novel coronavirus. After just a few weeks, the dogs could differentiate between healthy individuals’ urine samples and those from COVID-19 patients. But why were dogs trained to detect the disease from urine samples? Scientists believe that the odour of the urine of COVID-19 patients changes as SARS-CoV-2 damages blood arteries, kidneys, and other organs besides the lungs. Also, respiratory illnesses like COVID-19 change human body odour, which, researchers believe, will be caught by the strong olfactory sense of dogs. 

Man’s best friend in clinics? Not just yet!  
Scientists are still figuring out the chemical substances dogs use to detect the presence of an ailment. Furthermore, not all medical professionals would want to base their diagnosis on a dog’s abilities. That is why it is essential to combine human creativity with the special ability of dogs to find a solution. Andreas Mershin, a scientist at the Centre for Bits and Atoms, an initiative under the School of Architecture + Planning at Massachusetts Institute of Technology (MIT), wants to use man’s best friend to train machine learning algorithms for diagnosis. He is aiming to add an electronic nose to smartphones. Though this is seems a tad bit impossible, it may be a reality soon.