Dogs can be trained within weeks to detect COVID-19 infection, with a degree of accuracy comparable to a nose and throat swab test, new research has found.
Four dogs were trained to detect the virus in spring 2020 as part of a study conducted by the University of Helsinki in Finland.
The animals, previously trained to detect drugs, dangerous goods or cancer, each sniffed skin samples from 114 people who tested positive for the virus and 306 who tested negative.
They were able to detect the virus with 92% accuracy, according to the study.
The dogs also participated in a trial where they sniffed the samples of 303 incoming passengers at Helsinki-Vantaa International Airport between September 2020 and April 2021.
They correctly identified negative samples in 296 of 300 negative tests and identified three positive cases as negative.
It is one of a number of studies looking at dogs’ ability to detect COVID-19 – a clinic in Germany has dogs trained to detect the virus in human salivawhile a study in Thailand trained dogs to detect a volatile organic compound secreted in the sweat of patients.
The scientists said using dogs to detect viruses could be particularly useful in the early stages of a pandemic when other options are not available.
But they could also help contain an existing pandemic.
Writing in BMJ Global Health, the researchers suggested that “dogs could be used both in sites with high prevalence of Sars-CoV-2, such as hospitals (to prescreen patients and staff), as well as in low prevalence sites, such as airports. or ports (to pre-screen passengers)”.
The dogs were less successful in identifying the alpha variant, however, because they had been trained to detect the wild type.
The researchers said: “This observation is remarkable because it proves the powerful discriminatory power of scent dogs.
“The obvious implication is that training samples should cover all epidemiologically relevant variants.
“Our preliminary observations suggest that dogs primed with one type of virus can within hours be retrained to detect its variants.”