Trained dogs can detect the smell of Covid-19 with up to 94 per cent accuracy, new research has suggested, which could be a major breakthrough in testing.
The study by the London School of Hygiene and Tropical Medicine (LSHTM), has not yet been peer-reviewed but showed dogs were able to sniff out samples from people who were infected with Covid but were asymptomatic.
As well as sniffing out those who had low viral loads, the trained canines were able to identify different strains – both the dominant strain from last summer and the more recent Kent variant.
“What was great was the dogs that have been trained on the original variant transferred to the new (Kent) variant,” head of the department of disease control at LSHTM, professor James Logan, said.
“They could detect the new variant without any additional training.
“So, this gives us real hope and really suggests that dogs are able to detect different variants of Covid.”
Using more than 3,500 odour samples donated by the public and NHS staff, six dogs – Asher, Kyp, Lexie, Tala, Millie, and Marlow – from the charity Medical Detection Dogs took part in the double-blind trial.
The trained dogs were able to detect coronavirus-infected samples with up to 94.3 per cent sensitivity, which showed the ability to correctly identify positive cases and up to 92 per cent specificity, to correctly identify negative cases.
The research, which was partly funded by the Department of Health and Social Care, will enter another phase of the trial to see whether Covid detection is effective in a real-world setting.
The scientists will next test the sniffer dogs in spaces like airports and sports events. A method which, if found to be effective, could revolutionise the testing process.
Preliminary analysis using mathematical modelling suggested two dogs could screen 300 plane passengers in half an hour.
Using a rapid screen and test strategy, researchers said that individuals who are singled out by the dogs would then need to take a PCR test to confirm a diagnosis.
“These fantastic results are further evidence that dogs are one of the most reliable biosensors for detecting the odour of human disease,” chief scientific officer at Medical Detection Dogs, Dr Claire Guest, said.
“Our robust study shows the huge potential for dogs to help in the fight against Covid.”