Courtesy of the Pollitt Lab

As the coronavirus continues to spread globally, people who are wondering whether they have been exposed to the virus may have an answer in a new wearable virus-detecting clip developed by researchers at the Yale School of Public Health and the Yale School of Engineering and Applied Science.

Assistant professor of epidemiology Krystal Pollitt has been working in coordination with professor of chemical and environmental engineering Jordan Peccia’s lab for the past year to develop the FreshAir Clip — a small, silicone passive sampler that picks up aerosolized viral particles and can be analyzed in a laboratory setting to discern levels of exposure to SARS-CoV-2. The Pollitt lab has been testing the efficiency of the clip in capturing the airborne virus by enrolling health care workers at Yale New Haven Hospital to wear the device. They are now looking to expand trial enrollment to participants from Connecticut communities where COVID-19 prevalence is highest.

“The best way to determine if a person has exposure to a virus is to put a personal sampler on them, and then try to detect that virus of interest,” Peccia wrote in an email to the News. “The problem is that personal samplers are heavy and difficult to wear. They usually involve a sampler, a tube leading to a pump, and then a pump with batteries. The FreshAir clip gets around this problem because it is a passive sampler.”

Peccia explained that the virus simply settles on the polymer surface of the sampler and remains stuck there until participants return the clip to the lab for analysis after five days of wear.

Darryl Angel GRD ’25, a doctoral student in the Peccia lab, said that once the lab receives a used sampler, Angel extracts RNA  — the viral genetic material deposited on the clips — and analyzes the concentration of the virus using a technique called quantitative polymerase chain reaction, or qPCR, the same analytical technique used in saliva and nasal swab tests for COVID-19.

“The [FreshAir Clip surface] material is chemically inert, thus, when particles of interest deposit and sorb onto the surface we are later able detect the presence of viral particles or chemical constituents,” Angel wrote in an email to the News.

Because the samplers have a simple silicone face plate and no onerous electrical components, Peccia explained that the clips are low in cost and can be easily distributed to health care workers, teachers and the broader community to ultimately determine risks of exposure in various pockets of the population.

Pollitt said that the FreshAir Clip has been a natural extension of her work studying the relationship between personal exposures to environmental pollutants and human health. Her lab previously developed the Fresh Air wristband, a lightweight device using a similar approach as the FreshAir Clip that allowed it to measure exposure to airborne chemical contaminants. With this information, scientists were able to better understand how such exposure is related to the development and exacerbation of chronic diseases.

According to Pollitt, the researchers have used the Fresh Air wristband as a low-cost, non-invasive tool in China, India, South Africa, across the U.S. and Canada and in Europe as well. Pollitt explained that the Fresh Air wristband could be placed on everyone ranging from pregnant women to infants to the elderly because the bands did not impair mobility or impose a large burden. As a result, widespread distribution of the wristbands to low- and middle-income countries was possible.

In addition to widespread distribution of the Fresh Air wristbands, studies conducted on the efficacy of the FreshAir Clip in detecting viral particles yielded promising results, according to Pollitt. When clips were placed in COVID-positive patient rooms at Yale New Haven Hospital, they were able to detect the presence of SARS-CoV-2 within the room.

“We found this to be really interesting because we know that one of the infection control measures that is being highly recommended is enhanced ventilation,” Pollitt said. “Within the hospital network we had very high air change rates. Despite having those high air change rates, we were still able to detect airborne levels across the room.”

Pollitt explained that this initial study helped to clarify necessary changes to airflow in hospital settings where patients were infected with COVID-19.

As the researchers recruit more community participants to test the efficacy of the clip in a broader setting, Pollitt explained she is “very keen” to use the FreshAir Clip as a COVID-19 surveillance monitoring tool on a larger scale, specifically for high-risk groups.

Angel said that the “novel low cost and portable nature of the FreshAir Clip” can help determine the location of viral hotspots. This can in turn promote increased awareness of high infection rates in these areas and encourage behavioral changes to lower individuals’ risk of contracting COVID-19.

As of March 3, the CDC reports 28,456,860 cases of COVID-19.

Sydney Gray |