As if his talent were endless, dogs have proven remarkably effective at detecting Covid-19 with its super-sensitive nose.
Researchers led by the University of Veterinary Medicine at Hannover in Germany trained eight German Army sniffer dogs to identify odors associated with SARS-CoV-2, the virus responsible for Covid-19, in samples of human saliva and phlegm. After a week of training, they were able to differentiate between samples from infected and uninfected patients with 96 percent accuracy. This was reduced to 1,157 correct positive indications, 792 correct negative rejections, and around 63 incorrect indications or rejections.
The research is considered a small pilot study, but the promising results suggest that sniffer dogs may play some role in the detection and management of Covid-19 infections in the future. The study was published last week in the journal. BMC Infectious diseases.
“These preliminary findings indicating that pre-trained odor detection dogs can reliably, accurately and quickly discriminate between samples from SARS-CoV-2 infected patients and negative controls are truly exciting. We have built a solid foundation for Future studies to explore what dogs smell and whether they can be used to also discriminate between different disease time points or clinical phenotypes, “Professor Holger A Volk, Chairman of the Department of Veterinary Medicine and Small Animal Surgery at Hannover University of Veterinary Medicine he said in a statement.
Dogs that detect disease is not a new idea. Sniffer dogs have previously been used to detect Parkinson’s disease, malaria, Some forms of cancer, and a range of infectious respiratory diseases.
They can do this through their finely tuned nose that can detect chemicals known as volatile organic compounds (VOCs). Diseases can subtly alter the body’s metabolic processes and can lead to the production of different VOCs they enter the bloodstream and eventually are excreted in the breath or urine. Surprisingly, dogs are able to differentiate between the aroma of these tiny compounds, perhaps in concentrations as small as 0.001 parts per million. This is thanks to the 200 to 300 million olfactory receptors found in the nose of dogs (in comparison, humans have only 5 million). As this study shows, dogs appear to be able to identify VOCs associated with Covid-19.
It’s unclear how this knowledge could be implemented in the real world, but the researchers suggest it could be used in countries struggling to get hold of diagnostic tests.
“In countries with limited access to diagnostic tests, detection dogs could have the potential to be used for the mass detection of infected people. More work is needed to better understand the potential and limitation of the use of aromatic dogs for the detection of viral respiratory diseases, “the researchers conclude in their study.
