They discover that dogs can detect covid-19 with an accuracy of up to 94%

The  biodetection dogs can identify the smell of covid-19 in less than a second and with an accuracy rate of up to 94%, according to a preliminary study by the British association Medical Detection Dogs.

In a faster way than current PCR, these animals could become the new ally for detect coronavirus in public spaces, since a single dog can examine up to 250 people in an hour.

El study, led by the London School of Hygiene and Tropical Medicine (LSHTM), ensures that these dogs can detect people asymptomatic, with two strains different and with viral loads ups and downs.

Canine smell training

The Medical Detection Dogs team was the one who trained the dogs to identify covid-19 from Samples of body odor.

This charity has been training dogs' sense of smell since 2008. They teach them to detect odor changes in people with different diseases before their health deteriorates.

The samples (masks, socks and t-shirts) were sent by members of the United Kingdom's National Health Service. In total, they collected 3.758 samples of which they chose 325 positive and 675 negative.

The dogs were trained with them during ten weeks, presenting them those who had tested positive, as well as control samples from people who had tested negative.

The dogs were rewarded by correctly indicating a positive sample or by ignoring a negative one.

They also surpassed the important 'double blind' trial, in which the dog, the technician and the handler do not know which samples are positive or negative. This eliminates any bias the dog might perceive in indicating the correct response.

The dogs with the highest performance in the test detected the smell of the virus with up to a 94,3% sensitivity (which means a low risk of false negatives) and up to a 92% specificity (which means low risk of false positives).

In both cases, it is a higher precision than that recommended by the World Health Organization (WHO) for the diagnosis of covid-19.