Study Says Tracking Dogs Can Distinguish Coronavirus From 15 Other Respiratory Pathogens

JAKARTA - Sniffer dogs are able to distinguish the Sars-CoV-2 coronavirus from 15 other respiratory pathogens with high accuracy, according to a new study.

Research from an international team of researchers led by the German University of Veterinary Medicine Hannover (TiHo) has shown for the first time that a substance smelled by animals in people infected with the coronavirus is specific for Sars-CoV-2.

Dogs, with their amazing sense of smell, have been used in some public spaces such as airports during the pandemic to help reduce infections.

According to research published in the journal Frontiers in Medicine in November, sniffer dogs do not smell the virus itself, but the volatile organic compounds that are produced during metabolic processes following viral infection.

"It is known that infectious respiratory diseases can release certain volatile organic compounds, and this study shows dogs can recognize the unique pattern of volatile organic compounds from Sars-CoV-2," said Holger Volk, professor and head of the Small Animal Clinic at TiHo.

For the study, the researchers used 12 sniffer dogs that were trained with inactivated saliva samples from COVID-19 patients.

The animals were given saliva and swab samples as well as samples from infected cell cultures. It contains various viral pathogens, such as Sars-CoV-2, as well as influenza pathogens such as influenza A and B, rhinovirus and other coronaviruses such as the Mers coronavirus. Saliva from healthy volunteers and uninfected cell cultures served as control samples.

“In all three test scenarios, the average specificity was above 90 percent, which indicates that dogs can differentiate SARS-CoV-2 infection from other viral infections,” the researchers wrote in their study report. Specificity refers to the detection of negative control samples.

However, the mean diagnostic sensitivity, which indicates how well a positive sample is detected, has lower values in the three test scenarios compared to previous studies.

In order for sniffer dogs to distinguish coronavirus infection from other respiratory infections, it is necessary to include large numbers of samples of different viral respiratory infections in dog olfactory training, the study authors wrote.

Dogs are increasingly being used in several areas of medical research to detect odors, as they have been found to effectively detect both infectious and non-communicable diseases, such as various cancers, malaria, bacterial and viral infections.

To note, coronavirus sniffer dogs are being deployed at Helsinki airport in Finland, where volunteers can be tested by eight trained sniffer dogs sniffing a piece of cloth applied to the volunteer's skin.

Meanwhile, in France, a 2-year-old golden retriever named Pokaa has been trained to detect infections in a nursing home in Alsace, France. Here, people press a cotton cloth under their armpits and place it in a perforated metal box for Pokaa to sniff.