In a perfect world, we wouldn’t need to worry anymore about Covid-19. Fizzling cases, available vaccines, and the end of a public health emergency would have us believe the worst is behind us. And while that may be true, SARS-CoV-2, the culprit behind Covid-19, is entering its endemic era. This won’t make the virus any less deadly. The key question will be how do we keep tabs on the novel virus as it remains an unwelcome yet unseen permanent house guest?
Researchers at Washington University in St. Louis (WUSTL) believe they have an answer with a surveillance device that’s kind of like if a Covid-19 test kit had a baby with an air purifier.
In laboratory and real-life experiments, the proof-of-concept pathogen Air Quality (or pAQ) monitor was able to detect the virus and its different variants in a mid-sized room with startling good sensitivity in just minutes, according to results published Monday in the journal Nature Communications.
“There is nothing at the moment that tells us how safe a room is,” John Cirrito, the paper’s co-author and professor of neurology at WUSTL School of Medicine, said in a press release. “If you are in a room with 100 people, you don’t want to find out five days later whether you could be sick or not. The idea with this device is that you can know essentially in real-time, or every 5 minutes, if there is a live virus.”
The compact device, which stands 10 inches tall and one foot wide, employs a rather neat biosensor containing llama-derived nanobodies (a.k.a. mini-antibodies) that target the viral spike protein. This biosensor was originally created to detect amyloid beta, amino acids that are a biomarker of Alzheimer’s disease, but then adapted by the researchers for Covid-19 surveillance.
When placed in a room, the pAQ monitor sucks up the surrounding air at a flow rate of 1,000 liters per minute, which helps concentrate any amount of virus circulating, especially if concentrations are low. The viral particles are swept up into a sampler with cyclone technology, much like a Dyson vacuum, where it’s mixed with fluid and then delivered to the biosensor. If Covid-19 is present, the device sends out an alert warning the occupants of the room or other space being surveilled to take proper precautions.
Researchers tested out the pAQ monitor first in laboratory experiments where the device was placed in confined rooms contaminated with multiple inactivated SARS-CoV-2 variants: beta, delta, omicron, and Washington (WA-1). In these trials, the device was able to positively sniff out the virus with 77 and 83 percent accuracy. When tested in the apartments of confirmed Covid-19 positive patients and compared against virus-free controls, the device also demonstrated a similar range of sensitivity, stressing its potential for real-world application.
So when can you get your hands on this device? The WUSTL researchers are still running quality control tests. The initial trials only included two Covid-19 positive patients. But the researchers hope to commercialize the pAQ monitor in the near future. They also hope to add additional bells and whistles, such as detecting bothersome respiratory viruses like influenza.
“We are starting with SARS-CoV-2, but there are plans to also measure influenza, RSV, rhinovirus, and other top pathogens that routinely infect people,” said Cirrito. “In a hospital setting, the monitor could be used to measure for staph or strep, which cause all kinds of complications for patients. This could really have a major impact on people’s health.”
