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24th May 2021

Dogs can detect Covid in under a second, according to study

Danny Jones

Just some good boys and girls and their super shnozzes.

Dogs can detect Covid-19 in under a second: faster than a PCR (polymerase chain reaction) test and more accurate than a lateral flow test, according to a study published on Monday May 24.

Heckin’ good sniffer you got there, pups.

The research found that people who are infected with coronavirus give off a distinct odour, and while humans can’t necessarily pick up on it, these highly trained dogs can detect it with pinpoint precision. The study was carried out by the London School of Hygiene & Tropical Medicine (LSHTM) and six clever canines from Medical Detection Dogs (MDD).

Using a double-blind approach – i.e. neither the dogs nor the researchers could themselves know which was which – the MDD Covid detection dogs, essentially, had to sniff socks worn for 12 hours by volunteers across the UK. Gross but we thank you all for your sacrifice.

As noted in Linda Geddes’ story for The Guardian, dogs’ powerful mucus plays an important part in this super accurate, rapid detection. Their mucus dissolves odour molecules from the air and transports them to olfactory receptors in the top of their nose, before sending the signal to the brain. While humans have about 5 million of these receptors, dogs have up to 300 million.

MDD's Covid detection dogs

In conclusion, the study found that dogs could detect Covid-19 on clothing with up to 94.3% sensitivity, meaning they would correctly identify 94 out of every 100 people infected with the virus.

Furthermore, in addition to their unparalleled speed (under a second), the successfully sniffed socks included “people who are asymptomatic and also people with a low viral load,” according to Professor James Logan, who co-led the study. That level of accuracy and speed across 3,500 samples. Incredible stuff.

Of all six Covid detection dogs, a three-year-old golden labrador named Tala was the most accurate sniffer, achieving 94.5% sensitivity, and a specificity of 92% – i.e. the proportion of uninfected people that he would correctly identify. Well done, Tala!

MDD says that it takes around eight to ten weeks to train a Covid-19 detection dog. They are, of course, rewarded for their heroic efforts with a treat or some other kind of positive reinforcement like a ball. Most miraculously, this isn’t even the only site where tests like this are taking place, with Finland, France, Lebanon and Italy all using our beloved pets for Covid-19 detection.

Covid dog being trained in Rome

The charity’s CEO, Dr Claire Guest, has a long history with dogs, having worked with Hearing Dogs for Deaf People, before founding MDD in 2008. It was during this time that she met a woman who claims her pet Dalmatian diagnosed a malignant melanoma on her calf. Amazing.

Dogs have long been linked to detect illnesses including cancer and, recently, even malaria – Covid detection dogs are simply the next step. Back in 2002, Guest and orthopaedic surgeon, John Church, also proved that dogs can distinguish between urine from healthy people and those with bladder cancer.

Co-lead Logan believes that “dogs could be an additional tool that could be used as part of a kit to address the things that PCR and lateral flow tests can’t do. For example, dogs can screen people very quickly so they could be used in circumstances such as airports, or other public gatherings, stadiums, where lots of people have to be screened very quickly.”

Going simply off the same model and findings garnered from this study, it is estimated that dogs like these could be used at airports and other entry points into different countries to screen around 300 people in 30 minutes. Not all heroes were capes. Some wear collars.

We don’t need more reasons to love dogs more than we already do: they are simply the greatest creatures on earth – this research is yet more proof of that universal truth. High five (paw) to each and every one of you Covid detection dogs and all those involved.