Once again it seems like our furry friends can do more than just playing throw ball and wiggling their tails. According to a study conducted by London School of Hygiene and Tropical Medicine (LSHTM) it has been found that dogs can detect COVID-19 by sniffing urine or sweat samples.
The study showed that dogs were able to identify positive and negative samples with an average accuracy of 96 per cent. Another study published in PLOS One, done by experts at University of Pennsylvania has confirmed the same. This study was conducted using eight Labradors, Retrievers and one Belgian Malinois. The accuracy of detection of positive cases was confirmed to be around 95-97 per cent.
How Can Dogs Detect COVID-19?
Experts at Veterinary Council of India (VCI) explain the working of this detection method. In a word with Dr. Ayush Goel, JSO and Member of VCI, he explains, “Just like patients with diabetes have a sweet-smelling urine, coronavirus patients have a characteristic urine odour. This cannot be distinguished by a human nose but for dogs it’s quite easy. This is because their sense of smell and olfactory reception is stronger than ours.”
Exact reason why urine and sweat of corona positive patients smell different was explained last December by Professor Dominque Grandjean of the National Veterinary School of Alfort, France. “The virus forms certain molecules inside our body. This is done while it multiplies inside our body and produces its progeny. These leave the body through urine as catabolites or metabolites.”
Can Dogs Replace RT-PCR Completely?
Since the studies have been out, people are speculating whether dogs can completely replace RT-PCR or other testing methods. “I would say a big no. Yes it would help in reducing the number of RT-PCR and other testing and help to sniff out corona positive people among a big crowd. But, no test can be replaced”, adds Dr. Goel. Also, the dogs are still not able to detect false negatives and sometimes even identify negative tests as positive.
Indian army dogs sniffed COVID-19 patients. “Our dogs are well adapted to the real conditions. They have been trained and are still undergoing training to detect the cases. These dogs can be deployed at the airports and in the forces”, says Capt. Rahul Shishir, 20 K9 Army Dog Unit. However, as obvious as it sounds, domesticated dogs have no innate capability of identifying the coronavirus. They need to be trained. So only those breeds belonging to the “sniffer dogs” category can be trained.
Dubai had started using sniffer dogs last year to identify corona positive cases at its airport. Finland, Germany and Chile have also flagged off similar projects. However, one should note that these researches have been done in a simulated testing environment. The actual accuracy of this technique is yet to be tested out in the practical world.