Dogs can be trained to detect Covid-19 by sniffing human sweat, study suggests
December 10, 2020. Summarized by summa-bot.
Dogs can be trained to detect Covid-19 by sniffing human sweat, according to a proof-of-concept study published on Thursday. Many countries worldwide are exploring the possibility of using dogs as a reliable way to prescreen people for Covid-19.
(CNN)Dogs can be trained to detect Covid-19 by sniffing human sweat, according to a proof-of-concept study published on Thursday.
In the United Kingdom, a team from the London School of Hygiene and Tropical Medicine are training six dogs in the hope that they will be able to detect Covid-positive people -- even if they have no symptoms.
In this new study, researchers based in France and Lebanon took sweat samples from the underarms of a total of 177 patients from four hospitals in Paris and one in Beirut -- 95 had tested positive for Covid-19, while 82 had tested negative.
It was important that both the negative and positive samples came from the same hospitals so the dogs wouldn't be picking up on a particular "hospital odour," the researchers said.
Using some of the sweat samples, they trained 14 dogs that had been working as explosive detection dogs, search and rescue dogs or colon cancer detection dogs to take part in the study.
The scientists did not use dogs trained to detect illicit drugs because they could not rule out whether study patients who had provided sweat samples had used prohibited substances.
The researchers asked the animals to detect a positive Covid-19 sweat sample in one olfactory cone from a lineup of three to four cones that contained negative, or mock, samples.
Jacky and Bella, the two dogs that specialized in detecting colon cancer, had a 100% success rate in the 68 tests they completed.
"Even if trained dogs are able to correctly discriminate symptomatic Covid-19 positive individuals from asymptomatic negative ones, they should not be considered a perfect diagnostic test -- but rather a complementary tool," the study said.
The study, the researchers said, was a "promising first step" in providing some evidence that dogs may be able to detect Covid-19 samples collected from sweat.
However, the scientists said their study had some limitations, including that sweat samples had to be reused and researchers couldn't rule out that the dog was memorizing the scent -- although they didn't think memory played a major role.
For safety, the researchers did not use any samples for training or testing the dogs within 24 hours of collection.