Dog successfully sniffs Covid at the airport

Studies show that detection dogs should be used at airports and hospitals to detect early signs of a pandemic.

Trained dogs accurately found passengers infected with SARS-CoV-2The virus that causes Covid-19, according to a study published in the journal BMJ Global Health, To Professor Anu Cantere of Helsinki University Hospital.

This detection method is not only in the early stages of a pandemic where other resources may not yet be available. Continuous pandemicResearchers suggest.

Dogs have a very sharp sense of smell and can pick up scents at levels as low as one trillionth, far beyond the mechanical techniques available.

They are believed to be able to detect distinct volatile organic compounds released during various metabolic processes in the body, including those produced by bacterial, viral and parasitic infections.

Professor Cantere said National How you can actually use your dog’s skills.. “As an example, at the airport, dogs can sniff out all arriving passengers, and passengers that the dog identifies as positive are PCR tested.

“If the dog has experience as a scented dog, it will take two weeks to train the dog. This may provide a very valuable tool in the early stages of a pandemic.”

Preliminary data suggest that dogs can detect samples from patients with Covid-19 infection with accuracy comparable to standard PCR nose and throat swab tests.

Promisingly, the results of these lab data had to be replicated under real conditions. Therefore, researchers trained four dogs to sniff SARS-CoV-2 in the spring of 2020. Each dog was previously trained to sniff illegal drugs, dangerous goods, or cancer.

To test dog detection skills, 420 volunteers each provided four skin swab samples. Each of the four dogs sniffed 114 volunteers who tested positive for SARS-CoV-2 and 306 skin samples who tested negative for SARS-CoV-2. Samples were randomly presented to each dog over 7 trial sessions.

Overall, the diagnostic accuracy of all sniffed samples was 92%. The combined sensitivity (accuracy to detect infected) was 92%, and the compound specificity (accuracy to detect uninfected) was 91%.

Only slight changes were seen between the dogs.

About 28 of the positive samples were from asymptomatic individuals. Only one was mistakenly identified as negative and two were not sniffed. That is, 25 of the 28 (a little over 89%) were correctly identified as positive. The lack of symptoms did not appear to affect the dog’s performance.

Then, from September 2020 to April 2021, at Helsinki-Vantaa International Airport in Finland, we sniffed 303 passengers and sniffed dogs. Each passenger also took a PCR swab test.

PCR and sniffer results were consistent with 296 of the 303 actual samples.

Due to the relatively low prevalence of SARS-CoV-2 in airport passengers (<0.5%), dogs were also presented with 155 samples from people who tested positive for the PCR swab test.

Dogs correctly identified a little less than 99% as positive.

High scores support the use of detection dogs for screening, with the goal of excluding people who do not need the PCR swab test, according to researchers.

And they said, “For dogs, places with a high prevalence of SARS-CoV-2 such as hospitals (to select patients and staff in advance) and places with a low prevalence such as airports and ports (in advance). -Screen passengers). “They say this saves a lot of time and resources.

Researchers have acknowledged that dogs trained to sniff out other substances can mistakenly identify these substances as SARS-CoV-2 positive. They say that the required shelf life of training and spiked samples could also have affected the survival of volatile organic compounds.

An important finding was that dogs were less successful in correctly identifying alpha variants because they were trained to detect wild-type. But this is just an indication of how good dogs are at distinguishing between different scents, researchers say.

“This observation is noteworthy because it demonstrates the strong discriminating power of scented dogs. The obvious implication is that the training sample needs to cover all epidemiologically relevant variants. That is, according to our preliminary observations, dogs primed with a certain virus type can be retrained in a few hours to detect the variant. “

Updated: May 16, 2022 10:30 pm