Ever since the onset of the novel coronavirus disease in late 2019, the entire world has been in disrupt. Flights have been canceled, education stalled, international travel ceased; the world has been at a literal standstill since early 2020, all because you can not tell who may be infected with the SARS-CoV-2 virus. As of now, three different testing techniques are prevalent to establish the presence of coronavirus in a human body: Polymerase Chain Reaction (PCR) test, Lateral Flow Test (LFT), and the antibody (Serology) test. In spite of all these tests’ results being gradual, researchers around the globe are moving towards a newer and immediate source of testing: Dogs Sniffing COVID.
From the United States to Thailand and Britain to Germany, researchers have been busy employing sniffer dogs to train them into smelling coronavirus. According to a study, coronavirus has a specific odor, and dogs are being trained to identify that very odor. With their superior sense of smell, dogs have been known to help detect conditions as severe as cancer and diabetes; could coronavirus be an addition to these conditions?
The idea behind using dogs to trace out COVID-infected individuals relies on two primary things; dogs’ sensitivity, in controlled environments, has been greater than the PCR tests. Secondly, dogs sniffing Covid is quick; they can detect coronavirus on-spot and in real time.
It is common knowledge that PCR tests can, sometimes, return false-negative results for those infected with coronavirus; and not just that, it takes time to conduct these tests and get back their results. On the other hand, since a lot of infected patients are asymptomatic, thermal scanning cannot be trusted as a form of COVID screening. This is where dogs come in!
Tackling this pandemic has a lot to do with the way we test; faster and accurate results can mean better virus tracing, which will only help us limit the pandemic quickly. Dogs are on their way to prove their utility yet again in aiding humans trace their ailments.
Can Dogs Detect Covid?
According to an Australian researcher, Dr. Anne-Lise, dogs can detect COVID even during its incubation period. This could be a remarkable breakthrough for health workers globally, considering the late appearance of symptoms delays the diagnosis and, thus, its treatment causing a considerable upsurge in fatalities. An earlier diagnosis with the help of our canine friends can sure save numerous lives.
With up to 10,000 times better sense of smell than ours, dogs have for long had the ability to sniff out a lot for us. From finding narcotics hidden in deep crevices to assisting in finding signs of life in rescue missions, ‘man’s best friend’ has always proven its worth. Dogs have been regular members of bomb disposal as well as custom and border patrolling teams. Even on the medical frontier, dogs can sense the onset of Parkinson’s; they can know about the presence of several cancers like colorectal cancer and can also determine the existence of diabetes. Add to this, dogs sniffing Covid.
Dogs can even detect the virus in asymptomatic patients, and that too by just a sniff. The lungs and trachea of an individual infected with COVID produce a specific odor; dogs can detect this scent through the molecules in saliva and urine.
Can Dogs Smell Covid?
This is the modus operandi of dogs that researchers are trying to exploit to the benefit of the masses. As compared to 6 million for humans, dogs have an astounding 300 million olfactory (smell) receptors in their noses. These receptors allow dogs to be highly sensitive to smells, requiring very few molecules to snout out Covid as compared to a PCR test. Additionally, dogs can also be trained to learn several smell patterns for a certain compound that indicates the virus. This is where the key part of the ongoing researches lies in: Training dogs to identify coronavirus through sweat.
For places of mass gatherings like airports or stadia, it is virtually impossible to carry out PCR tests for everyone and make them wait untill results are back. This could possibly take up a lifetime. On the contrary, these cute dogs have been trained to identify the presence of the virus in sweat-induced cotton swabs. This is why they are used by some and may be used by all, as virus scanners at crowded places in the near future. True, dogs may never formally replace PCR as a primary test, but they can certainly complement it and other forms of testing especially in places where immediate results are needed.
Training Dogs to Detect Covid
No specific breed of dogs has been used for the multiple researches going around the world. From Labradors to German Shepherds and Border Gypsies to Golden Retrievers, numerous breeds have been employed to detect the virus. It is worth noting that almost all dogs have returned identical results. Initially, these experiments were carried out by training dogs to trace out the virus from urine and saliva samples; the dogs returned a staggering 96% accurate results at one of the research programs at the University of Pennsylvania. The numbers and accuracy gave a tremendous fillip to the research, and dogs are now being trained to detect the virus from sweat. Detecting COVID from the sweat present on clothes could make the whole process much quicker and efficient. It would hardly require any costs or time and the dogs could just sniff a passerby and signal the presence of the virus. This could prove to be a game-changer.
To start off the process, the dogs were presented with positive samples and then given treats so they could memorize the odor and relate it with the reward. Several studies are taking place worldwide, with some using cotton balls wiped on the armpits and socks of Covid-positive individuals while others have been using sweat-stained shirts. In the next step, the participant dogs were presented with different items, including sweaty shirts and other material that could distract them. All the dogs knew to keep trudging through different things until they sniffed the virus from the sweaty shirts. Sweaty shirts from Covid-negative individuals were used, too, but the dogs, in most cases, could differentiate between the two.
Dogs have the faculty to identify the organic compound of the virus present in sweat, saliva, or urine. These compounds are unique to the virus, and with dogs’ superior sense of smell, they are able to detect the presence of coronavirus. Two of the ongoing studies have proved the same.
The first study showed dogs to correctly find the COVID-positive sample in 82-94% of the cases, while the other study showed this metric to be a whopping 97%. As for finding the samples that did not have Covid, the first study showed dogs to find this correctly 76-92% of the time, while the second study showed the results for the same to be 91%, respectively.
These are highly encouraging numbers and almost equal the accuracy of the PCR test, if not better. These studies are yet to be peer-reviewed, though. Nevertheless, they certainly do pave the way for future researches. The corona scent that these dogs pick up cannot be smelled by humans; however, based on the detecting mechanism of dogs, electronic sniffers could be set up. Along the lines of breathalyzers, Covid detectors could also be made with the help of sniffer dogs.
Countries like Finland and the United Arab Emirates have already started deploying sniffer dogs at various airports to screen people on a massive scale for coronavirus. Unlike other forms of testing, dogs have helped to save time by merely sniffing at passersby and detecting Covid. On average, 2 dogs can screen up to 300 people in just half an hour. This seems to be the way forward for now as the world desperately looks on at healthcare workers and researchers to be able to resume their normal pre-Covid lives.
According to another research conducted in Britain, six dogs were trained to detect the virus. They correctly returned 88% of coronavirus cases. But they also incorrectly picked 16% of people who were COVID-negative. These, by no means, are discouraging results. The sensitivity levels certainly match almost all forms of testing available to us; however, the specificity can really set off all the results.
Experts, thus, recommend that dogs alone may not be enough to detect the virus, and the results may not be entirely reliable. Without a shadow of doubt, dogs are a vital addition in the fight against coronavirus, but it’s vital for now to back up these results with PCR or other forms of more reliable tests. For now, dogs can be—and are being—used at stadiums during sporting events, at airports, and other spots of mass gatherings to screen people for the virus at a quicker rate.
Note: The information presented here is for general purpose and cannot be taken as authoritative, despite being cautious with our research, facts, and sources.