The team from the Yale School of Public Health call the device the Fresh Air Clip. Originally developed to detect airborne pollutants and pesticides the lightweight detector requires no power source and is easy to 3D print.
The clips are simple, consisting of a magnetic fastener to attach them to a lapel or pocket. Inside the clip is a slip of film made of a substance called polydimethylsilixane, or PDMS, which catches the particles.
According to the researchers the device could allow the tracking of Covid exposure in high-risk workplaces such as hospitals and restaurants.
"This is really a complementary tool to all the other infectious control measures that are available," the team's leader Professor Krystal Pollitt told The Independent. "We know that masking is an incredibly effective means for protection; we know that decreased occupancy and ventilation is effective.
"This is just another tool that can be used to alert people of potential exposure, and to highlight spaces that need more of these other controls to make sure that exposure is minimised."
Despite the research team’s confidence in the new tool its adoption is limited by the availability of PCR tests which are necessary for analysis of the clip. Prof Pollitt and her colleague Dr Dong Gao spent two years testing the wearable’s ability to detect coronavirus.
They placed the clip in a rotating drum full of particles of a virus with similar properties to SARS-Cov-2, which causes Covid-19, designed to simulate the way airborne viruses move through spaces.
“As soon as Covid started we appreciated the potential for it to be airborne,” said Prof Pollitt. “That's when we realised we should be using this device to also sample airborne virus.”
After developing the device to detect the virus the team tested its efficacy by distributing the clips to 62 volunteers who wore them five days each.
At the end of this time each device was returned to a lab where its film was analyzed via a PCR test. Five of the clips later showed traces of SARS-Cov-2; four of them were worn by restaurant staff, while the other's wearer worked at a homeless shelter.