Ceiling mounted sensor can ‘smell’ Covid-19 on infected people

Led by researchers from the London School of Hygiene & Tropical Medicine (LSHTM) and the biotech company RoboScientific with Durham University, the study tested devices with organic semiconducting (OSC) sensors which could potentially be used as a Covid-19 screening tool.

They envisage it being used in public spaces, like inside commercial aircraft, where the risk of transmitting the disease can be high.

The team found that Covid-19 infection has a distinct smell, resulting from changes in the volatile organic compounds (VOC) which make up body odour – generating an odour ‘fingerprint’ that the sensors can detect.

This study used body odour samples from socks worn and donated to the team by 54 individuals – 27 Covid-19 positive individuals who were asymptomatic or had mild symptoms, and 27 uninfected individuals.

These samples were analysed by RoboScientific’s Model 307B VOC analyser fitted with an array of 12 OSC sensors.

The OSC sensors captured the odour profile of the samples, having been tuned to be sensitive to the VOCs associated with Covid-19 infection, primarily ketone and aldehyde compounds.

Over two days of testing the samples, the researchers found the sensors were able to distinguish between infected and uninfected samples. Based on early tests, they believe the device can detect the presence of Covid-19 infection more accurately than any other diagnostic test available.

Professor James Logan, head of the Department of Disease Control at LSHTM, who led the study, said: “These results are really promising and demonstrate the potential for using this technology as a rapid, non-invasive test with incredible accuracy. However, further testing is required to confirm if these results can be replicated in real-world settings.

“If these devices are successfully developed for use in public places, they could be affordably and easily scaled up. They also could protect people against future disease outbreaks, with capability to develop sensor arrays to detect other diseases within a number of weeks.”

Professor Steve Lindsay, from the Department of Biosciences at Durham University, said: “Many diseases have a distinct smell associated with them. We started our research with a blank sheet of paper and asked the question: Does Covid-19 have a distinct smell?

“We ended the research showing a clear separation between the odours of people infected with the virus and those uninfected. Covid most definitely has a very distinct smell. This is real discovery science and very exciting for the development of screening methods for the disease.”

The Cambridgeshire-based start-up RoboScientific is now trying to use the technology to develop a handheld device that could be used for early disease detection and could detect if a person is Covid-19 positive from their body odour.

In May, it was announced that a machine learning algorithm has been developed that can detect which patients with Covid-19 might get worse and not respond positively to being turned onto their front in intensive care units.