Texas-based InspectIR Systems’ breath test for Covid-19 — the first such test to get emergency use authorization from the Food and Drug Administration — will probably have limited use at first. But it is nevertheless an important step toward expanding the toolkit available to prevent outbreaks of Covid and any future viruses at big sports and entertainment events and other places where hundreds of people gather.
The technology is beautifully simple. A patient exhales into a cardboard straw connected to a suitcase-sized device, which analyzes the sample in less than three minutes.
The InspectIR device can process only about 160 samples a day. The company reportedly has limited inventory. And so far, the test must be operated by specially trained technicians. This explains why its use will be limited at first.
But its authorization expands and fortifies the testing infrastructure. A breath test that is cheap, easy to use, fast and capable of screening hundreds of people a day could bolster efforts to quell big outbreaks.
Covid screening is done in various ways, of course. At one end of the spectrum is wastewater testing, which provides an early signal that cases are rising in an area. At the other end are PCR molecular tests, which accurately detect genetic material from the virus in a nasal swab. These are widely considered the gold standard, but they can take hours, sometimes days to turn around.
At-home tests, which typically look for bits of viral protein (antigens), are reasonably accurate and fast. In theory, they can allow for widespread testing, but they can be expensive, and 15 minutes can be a long time to wait for “fast” results, especially if a large number of people need to be screened at once. Last summer, I waited more than an hour to be let into a comedy show that required rapid testing for entry — and the audience included only about 100 people.
What’s missing is a test that is cheap, fast and accurate enough to weed out most positive cases in a large crowd. This is where breath-based tests can come in handy.
Deep in our lungs, gases are exchanged between the air that’s inhaled and the air that’s breathed out — a mix of more 200 compounds. InspectIR’s test looks for five specific compounds that are present if someone has Covid.
In a study of 2,409 people with and without symptoms, the breath test correctly identified 91.2% of those infected with the virus, according to data the FDA released, and also correctly identified 99.3% of negative samples. (Those results held up against the omicron variant.)
The 91.2% accuracy in detecting positive samples may sound somewhat low, but it is high enough for a test that’s meant to quickly screen crowds. The idea is to catch enough infections to prevent a superspreading event.
People who tested positive would presumably go on to take rapid antigen tests to confirm their infections.
Breath tests aren’t without detractors. Some scientists question whether it’s possible to find a signature of breath compounds that’s truly unique to one virus or disease. And although instrumentation could be easy to operate and cheap to run at scale, setup costs could be prohibitive.
But this technology will be steadily refined. Several researchers in the US, with support from the National Institutes of Health’s Rapid Acceleration of Diagnostics Initiative, are getting closer to launching their own devices.
The pandemic has provided a unique opportunity to revolutionize diagnostics for diseases well beyond Covid. Developing breath-test technology could fill out the testing infrastructure to make us better prepared for any kind of outbreak.
Bloomberg
