Does the idea of attending an arena-sized concert with 50,000 other fans sound scary right now? Heading out to enjoy your favorite megastar is just a fantasy at the moment. But what if there was a way to test everyone for COVID-19 quickly, before they enter the venue?

Recent findings published in the journal Lab on a Chip suggest that this kind of rapid pathogen testing is possible. Brian Cunningham, professor of electrical and computer engineering at the University of Illinois at Urbana-Champaign, led a multi-institutional team of researchers studying a smart-phone-based testing device. The study found that the device can accurately detect pathogens in nasal swabs from horses in as little as 30 minutes.

The device, which costs about $50, clips onto a smartphone. The nasal swab is deposited onto a chip that slides into the device, which then injects a fluorescent dye into genetic material within the sample. When attached to the smartphone, the phone’s camera detects the fluorescence that indicates the presence of specific pathogens.

The study focused on five viral and bacterial pathogens that cause infectious respiratory diseases similar to COVID-19 in horses. The findings show that the device correctly diagnosed pathogens in the horse samples in 30 minutes, with comparable accuracy to a traditional laboratory test.

“Cloud computing via a smartphone application could allow a negative test result to be registered with event organizers or as part of a boarding pass for a flight,” Cunningham explained. “Or a person in quarantine could give themselves daily tests, register the results with a doctor, and then know when it’s safe to come out and rejoin society.”

Further development and clinical studies of the device may make it possible to test humans for COVID-19 quickly and accurately. That could have multiple implications for managing the pandemic. It could even mean that safe attendance at large-scale events might be possible sooner than expected.