At Chulalongkorn University in Thailand, Labradors are being trained to sniff out Covid-19 in humans, as part of a global corps of dogs to be used to detect the virus. Preliminary studies, conducted in several countries, suggest that their detection rate may surpass that of the rapid antigen testing often used in airports and other public places.
The hope is that dogs can be deployed in crowded public spaces, like stadiums or transportation hubs, to identify people carrying the virus. Their skills are being developed in Thailand, France, Britain, Chile, Australia, Belgium and Germany, among other countries. They have patrolled airports in Finland, Lebanon and the United Arab Emirates.
Sniffer dogs work faster and far more cheaply than polymerase chain reaction, or P.C.R., testing, their proponents say. An intake of air through their sensitive snouts is enough to identify within a second the volatile organic compounds that are produced when a person with Covid-19 sheds damaged cells.
Some methods of detection, like temperature screening, can’t identify infected people who have no symptoms. But dogs can, because the infected lungs and trachea produce a trademark scent. And dogs need fewer molecules to nose out Covid than are required for P.C.R. testing.
The Thai Labradors are part of a research project run jointly by Chulalongkorn University and Chevron. The oil company had previously used dogs to test its offshore employees for illegal drug use. A dog’s ability to sniff out Covid-19 is, in theory, no different from its prowess in detecting narcotics, explosives or a Scooby snack hidden in a pocket.