In countries such as Belgium, Brazil, Chile or the United Arab Emirates, train dogs, which are used in various airports, to detect Covid-19.
According to an international research team, led by Dominique Grandjean at France’s Alfort National Veterinary School, which has been training dogs to detect traces of the new coronavirus (SARS-CoV-2) in the sweat of infected people, the majority of dogs have absolute precision.
Coronavirus detection dogs are already being trained in countries such as Belgium, Brazil, Chile, or the United Arab Emirates, which are used at various airports.
In addition, detector dogs could identify SARS-CoV-2 in infected people while they were still asymptomatic. What exactly dogs smell, we don’t know. Volatile organic compounds (VOCs) emitted in sweat samples are a complex mix. Therefore, it is likely that the dogs are detecting a particular profile rather than individual compounds.
Sweat is used for testing, as it is not considered infectious for Covid-19. This means that it presents less risk when handling samples.
At the moment, it seems that dogs do get infected with the coronavirus, but they do not have symptoms, and it does not seem that they can infect humans. To further reduce the potential risk of transmission to people and dogs, the apparatus used to train the dogs does not allow any direct contact between the dog’s nose and the sweat sample. The dog’s nose enters a stainless steel cone, with the sweat sample in a container behind. This allows free access to volatile olfactory compounds but without physical contact.
Additionally, all dogs trained to detect Covid-19 are regularly screened using nasal swab tests, rectal swab tests, and blood tests to identify antibodies. So far, none of the detector dogs have been found infected.
The ability of dogs to detect Covid-19 is not so surprising considering that they already help detect hypoglycemia in diabetics, or have been used to detect some types of cancer.