The most common test to determine if someone has tuberculosis hasn't really changed since the late 1800s. The process relies on phlegm.

"It's a nasty substance," says Adithya Cattamanchi, a pulmonologist at UC Irvine. "No one likes it, right? You don't like to cough it up. Health workers don't like to work with it. It's difficult to work with in the lab because it's so viscous." In addition, not everyone can produce phlegm easily, including children, the elderly and those weakened by disease.

The phlegm is then examined under a microscope for the telltale tuberculosis bacteria. But the test is imperfect and imprecise. Sometimes patients are told they have TB when they don't. And about half the time, the test misses actual TB cases.

"So for a long time, we have been trying to make the diagnosis of tuberculosis easier, cheaper, and quicker," says Alfred Andama, a microbiologist at Makerere University College of Health Sciences in Uganda.

That desire was fulfilled last year when the Chinese company Pluslife announced a new tuberculosis test called the MiniDock MTB. It works by taking a sample of someone's phlegm or — if the patient is unable to produce phlegm — a mere tongue swab, heating and spinning it down, and then machine scanning it for DNA from the TB bacteria. It's faster than conventional tests and is portable, allowing health workers to use it in a wider variety of settings.

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The new test followed from a burst of innovation during the pandemic, a period when swab-based testing for COVID-19 improved dramatically due to an infusion of effort and cash from researchers and industry.