Does the person next to you smell like they have COVID-19?
If you ask this question to a human on the street, they’d probably furrow their brows and find a reason to excuse themselves quickly.
But if you ask this question to a dog, well, they would also be confused because they don’t speak English.
However, it seems that our beloved canines have a special power that none of us possess: the ability to sniff out (literally) the coronavirus.
Study Shows That Dogs Can Detect Whether Travellers Have COVID-19 Even If They Are Asymptomatic
A new study has shown that trained dogs are able to detect more than 90% of COVID-19 infections, even in patients who are asymptomatic.
The research, published today (24 May), was conducted at the London School of Tropical Medicine.
Since dogs have already shown in the past that they can detect diseases like cancer and malaria, researchers wanted to establish whether these canines could detect a distinctive odour emitted from someone who is COVID-19 positive but asymptomatic.
This is how the test worked:
- Dogs were trained to indicate either a presence or absence of the chemical compound associated with COVID-19
- Researchers gathered clothing and face masks samples from patients with mild or symptomatic COVID-19
- These samples were presented to the trained dogs in laboratory tests and they were asked to identify which were COVID-19 positive
Overall, the trusty canines were able to identify between 94% and 82% of COVID-19 samples. Indeed, they are the good-est (or goody-est?) doggos.
These detection rates, coupled with traditional polymerase chain reaction (PCR) tests, may be able to detect 91% of cases at airports, according to a model devised by researchers.
This would result in a 2.24 times lower rate of transmission than with PCR tests alone.
Trained Not to Identify False Positives
You might be thinking: how can an animal which often spends hours chasing its tail be able to accurately detect a COVID-19 infection, when even PCR tests get it wrong every now and then?
Well, what researchers did is they essentially “hacked” the dogs’ reward system by giving them treats even when there were no COVID-19 samples in a test.
So, a dog understands and gets a reward when he detects a correct positive, but also a correct negative.
And tada! By doing this, researchers conditioned the dogs not to identify “false positives”.
Dogs Are “Significantly Quicker” Than Tests; Could Replace Travel Quarantine
James Logan, co-author of the study, said that dogs were “significantly quicker” than other tests in detecting COVID-19.
If implemented at airports, this could negate the need for travellers to quarantine.
The researchers gave an example of a plane carrying 300 people arriving at an airport. Statistically, less than 1% of them would likely be COVID-19 positive.
Under the current quarantine regulations imposed by some countries, all 300 would need to isolate.
But if trained dogs sniffed out potential infections beforehand, only a maximum of 35 people on board would be indicated as positive and isolated.
They would then be given a PCR test to confirm their infection. Of the 35 isolated, only three would typically test positive in the end.
However, the research has yet to be peer-reviewed, and dogs need to be shown to reliably and consistently detect asymptomatic infections before it can be put into place at places like airports and train stations.
But maybe, just maybe, when leisure travel finally returns in 2035, an adorable doggo, not a quarantine order, will be the one greeting you at the airport.
Feature Image: rfranca / Shutterstock.com (Image is for illustration purposes only)
