Sniffer DOGS is better at detecting Covid than real tests, says study

Sniffer dogs are even better at detecting Covid than testing, according to the strongest evidence yet.

During the pandemic, scientists said dogs’ acute sense of smell could be used to detect carriers of the virus.

However, the promising laboratory results from dogs exposed to samples in highly controlled situations had to be replicated in real-world conditions.

New results from the University of Helsinki show that Labrador Retrievers and White Shepherds can recognize 97% of positive cases.

The study says trained dogs are 99% accurate when confirming who among airport passengers is virus-free.

In contrast, studies show that lateral flow tests detect up to 72% of cases, while PCR tests are accurate between 85% and 98%.

Finnish researchers said the dogs could be a “valuable tool to contain the epidemic” when used at airports and other public gatherings.

The results show that dogs can recognize 97% of positive cases. The study says trained dogs are 99% accurate when confirming who among airport passengers is virus-free. Pictured: Kosti at Helsinki-Vantaa International Airport

New results from a study at the University of Helsinki show that dogs can recognize up to 97% of cases and are 99% accurate in confirming who is virus-free. In the photo: White Shepherd ET puts a paw on the center number two champion in the rehearsal room, indicating that he is Covid positive.

The researchers said their findings suggest that dogs that can smell malaria, Parkinson’s and cancer may serve as a method of screening for viruses when tests are not available, such as in the early stages of a pandemic. Pictured: Purpose-built cells at Helsinki-Vantaa International Airport in Finland, where dogs sniff samples from passengers

Dogs were never used in the pandemic response in the UK. But they were stationed at Paddington Station in London as part of evidence that they could be taken to airports.

Sniffer dogs are already used to warn against seizures, cancer and Parkinson’s.

Dogs can smell one part per trillion, which is the equivalent of one teaspoon of sugar in two Olympic swimming pools.

They are thought to be able to detect substances that are quietly released from the body when sick.

The Helsinki team trained four dogs – Labrador retriever Silja, Rele and Kosti, and a white shepherd named ET – to monitor for Covid in the spring of 2020.

The dogs were exposed to skin samples (neck, forehead and wrist swabs) from 114 volunteers who tested positive for the virus.

They were also exposed to hundreds of non-Covid samples.

During their training, the dogs were 92% accurate in recognizing the infected and 91% correct in confirming that one was Covid negative.

Dogs have reported a positive case of stretching their paws or sitting down.

And even though a sample was from someone who had no symptoms (89%), their olfactory skills were almost equally good.

In contrast, studies show that lateral flow tests are missing in 20% to 80% of positive cases.

To test the dogs in a realistic scenario, they sniffed 303 passengers arriving at Helsinki-Vantaa International Airport in Finland between September 2020 and April 2021.

Each of the passengers had also had a PCR test done.

The results, published in BMJ Global Health, show that the dog detection and PCR result matched in 98% of cases.

Previous research by British researchers from Durham University and the London School of Hygiene and Tropical Medicine found that dogs can detect up to 94% of cases, making them significantly more accurate than rapid lateral flow tests.

British researchers said the two dogs could film 300 passengers getting off the plane to Kovid in just 30 minutes. Pictured: A sniffing dog and paramedic demonstrate how dogs can be used to detect Covid in the public in public places

Dogs were never used in the pandemic response in the UK. But as part of testing to determine if the dogs could effectively sniff out the disease using £500,000 of taxpayer money, the dogs were lined up at London’s Paddington Station (pictured with the Duchess of Cornwall and former health minister Matt Hancock)

Dogs sniffing samples in special-purpose cabins at the airport confirmed that 296 of the 300 passengers were Covid negative (99% success rate).

However, they failed to see only three PCR positive passengers.

But the researchers said one of those passengers tested negative on a second PCR, and one tested positive but is no longer contagious.

Experts said some of the differences in dogs’ olfactory abilities were due to the fact that they were trained to detect the original virus strain, not Alpha.

Due to the low positivity rate at the airport, the dogs received 155 samples from people infected with Covid. The dogs correctly identified 99 percent of these swabs.

Combining the airport and positive samples, the dogs saw 97 percent of those with the infection and 99 percent of those without the virus.

The researchers said this demonstrates the “robust discriminative power” of the dogs’ olfactory abilities and should be trained to detect all circulating variants.

They said a dog can be retrained to detect a new species in “a few hours”.

In separate analyzes, the researchers modeled how accurate dogs would be at detecting the virus when four in ten people were infected during a pandemic, such as in a hospital, and only one percent were infected, such as at an airport.

They estimated that when the prevalence was high, dogs would play 88% of positive cases and 94.5% of negative cases.

If the prevalence of the virus is low, dogs will notice about one in 10 people infected, confirming almost all adverse cases.

The researchers suggest that dogs could be used for screening to save time and exclude people who don’t need a PCR smear to test skills.