Watch: 'Electronic nose' sniffs out the coronavirus
A "electronic nose" could sniff out the coronavirus in just 80 seconds.
Scientists from the Weizmann Institute in Israel are adapting pre-existing technology in the hope it could one day be used at the doors of mass events.
Despite UK infection rates slowly rising and new variants emerging, Boris Johnson has said he can see "nothing in the data" to delay England's exit from lockdown on 21 June.
With nightclubs and festivals just a few of the public spaces set to open up, many people are concerned this will lead to a dreaded third wave, particularly as up to a third of coronavirus carriers develop no symptoms.
Read more: Bees could be trained to smell coronavirus
The nose picked up on coronavirus carriers, even asymptomatic ones, up to 75% of the time.
While the research is still in its infancy, the scientists believe the "payback" could be "huge".
This comes after a team from the University of Pennsylvania reported their electronic nose sniffs out cancer with up to 95% accuracy.
"Every disease has an odour," said study author Professor Noam Sobel.
"This is because diseases change metabolic processes [the chemical reactions that take place within cells], metabolic processes have metabolites [end products], metabolites have a smell."
Animals, from dogs to bees, are being trained to smell the coronavirus.
"Given the scale of the pandemic, however, animal deployment is a challenging situation," the scientists wrote in the journal PLOS ONE. Meanwhile, electronic noses "can be deployed at scale".
The team's so-called eNose "contains an array of sensors" that pick up different chemicals.
Rather than focusing on an individual's breath, like similar devices, the Weizmann team's technology detects odours up an individual's nostrils.
"This device generates a patten, reflecting every odourant it smells," said Professor Sobel.
To put the eNose to the test, the device was used on 503 people who had a "lengthy exposure to a verified COVID-19 [the disease caused by the coronavirus] patient or were experiencing persistent symptoms".
Of these, 27 later swabbed positive via the gold-standard polymerase chain reaction (PCR) test.
Overall, the eNose picked up on two-thirds (66%) of the coronavirus-positive participants, rising to three quarters (75%) among those without any symptoms – "at a level significantly better than chance".
This accuracy is "not far off" that of PCR tests, with the eNose giving results "instantaneously rather than days later".
The scientists have stressed their study was "proof of concept", with further research being required.
"In many ways this is a shot in the dark," said Professor Sobel.
"The right way to do this would have been to first characterise the smell of the disease and then optimise the electronic nose for that particular smell, but it takes a lot of time.
"That said, rather than sitting idle, we decided we would try."
If the eNose proves to be effective in future studies, it would "provide extensive relief in the COVID-19 pandemic".
"The payback will be so huge if it works," said Professor Sobel. "We could get an answer in 80 seconds."
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