JUDY WOODRUFF: Although rare in the U.S., before COVID-19, tuberculosis was the world's
deadliest infectious disease.
John Yang tells us of one scientist's journey to the discovery both of a new tool to fight
T.B. and of her own potential.
It's part of Breakthroughs, our series on invention and innovation.
JOHN YANG: In many ways, Mireille Kamariza's life journey is longer than just the miles
from her native Burundi to the United States.
Now 31 years old, she's a fellow at Harvard, has degrees from Berkeley and Stanford, and,
through her Silicon Valley startup, is working on a potential breakthrough diagnostic tool
to fight tuberculosis. But if someone had told her as a teenager in Africa that this
is where she'd be now?
MIREILLE KAMARIZA, Junior Harvard Fellow: What are you drinking? Can I have some?
(LAUGHTER)
JOHN YANG: Growing up in Burundi, a small landlocked country in East Africa, Kamariza
remembers loving science, particularly astronomy. Frequent power outages gave her plenty of
opportunities to marvel at the night sky.
MIREILLE KAMARIZA: You would see, like, amazing bright stars. And I used to wonder, what's
there? Who's there? Is there a light out there? I mean, is there someone shining a light towards
us? Is that why we're seeing it? The unknown is what attracted me.
JOHN YANG: When she was 17, she joined her older brothers in California to pursue her
education. As a French speaker, she struggled.
MIREILLE KAMARIZA: I knew how to say thank you and hi. That was about the extent of it.
And so, when I moved here, it was like landing on Mars.
JOHN YANG: She enrolled at a community college, with no plans beyond study and chemistry,
graduating and getting a job.
MIREILLE KAMARIZA: That's really the end of it. And there wasn't any imagination that
I could be a scientist.
A scientist is not someone that looks like me. I knew that growing up. It would have
been an unrealistic expectation.
JOHN YANG: But a French-speaking female chemistry professor from Africa encouraged her to transfer
to U.C. San Diego. There, she found another role model in one of the few women of color
on the faculty.
MIREILLE KAMARIZA: My mentor at U.C. San Diego is the one who said: "You know, I'm a scientist.
You could be one too."
JOHN YANG: She encouraged Kamariza to apply to graduate school at Berkeley. Again, Kamariza
was skeptical. Again, she got in.
Sort of every step along the way, you thought, well, this isn't going to happen. This -- I
will do this, but this isn't going to happen.
MIREILLE KAMARIZA: Yes, that's exactly right.
JOHN YANG: But then it did happen.
MIREILLE KAMARIZA: And then it did. And here we are.
JOHN YANG: During her doctoral studies at Stanford, she turned to a disease endemic
in Burundi and other developing countries.
MIREILLE KAMARIZA: I grew up knowing that tuberculosis is a disease that you could die
from. And it's a disease that is prevalent in my community.
JOHN YANG: Before COVID-19, tuberculosis was the world's deadliest infectious disease,
killing 1.4 million people in 2019, far more than HIV/AIDS.
Like COVID-19, it's transmitted through the air when an infected person speaks, sings,
or coughs.
Harvard infectious disease specialist Dr. Eric Rubin says T.B. persists, in part, because
it's hard to diagnose.
DR. ERIC RUBIN, Harvard University: T.B. in most people looks like pneumonia, and it's
not that distinguishable from other forms of pneumonia.
It also can look like cancer because it's a very slowly progressive disease and people
have some of the same symptoms that they would from smoking-induced cancers. So, unless you
think of it, it's hard to come up with. And then, once you think of it, the diagnostic
tests aren't terribly good. They're just not that sensitive.
JOHN YANG: Rubin says there are better tests, but they require weeks or months to produce
results, or more expensive specialized equipment and training.
DR. ERIC RUBIN: If you look across the world, people are missed at the stage of diagnosis.
Or, if they are diagnosed, they have already disappeared and gone back home before the
tests are available and, therefore, they get lost.
JOHN YANG: With those missed diagnoses, patients get sicker, and may go on to infect others.
That's where Kamariza's discovery comes in.
She developed a cheap, simple technique for diagnosing T.B. that could be used in low-resource
settings and provide quick results.
DR. ERIC RUBIN: What Mireille and her colleagues have found is a method for essentially lighting
up the bacteria. So, instead of searching through a slide for those rare bacteria that
hopefully stained with a laborious stain, you can simply add her reagent, and the bacteria
become fluorescent in a very specific way.
MIREILLE KAMARIZA: Not only is it simpler to use, is it faster to use, but it also can
tell you whether the pathogen you have is drug-resistant and even what kind of resistance
you have, what resistance you have against what drug.
And all of that can be done at the point of care.
JOHN YANG: Before it can widely used, Kamariza's new diagnostic technique must undergo clinical
trials. But those, like so many other things, have been put on hold by COVID-19, which underscores
a larger problem.
Many who study T.B. are worried that, during the pandemic, years of steady progress against
the disease have been set back, and it could be years before things get back on track.
DR. ERIC RUBIN: Part of what's going to slow it down is, most of the world doesn't have
vaccine. So it's going to be a while until we're able to rebuild the systems that we
need.
JOHN YANG: Kamariza's mission says her mission now is to get this new diagnostic tool through
clinical trials and to the people who need it.
MIREILLE KAMARIZA: I'm hoping that not only would it get to where it needs to be, but
I'm also hoping that the story of how it was made will inspire the people in those communities,
whether they're young boys or young girls.
And they could be inspired by my own story of coming from Burundi and making it here.
JOHN YANG: And so they, too, can see what a scientist looks like.
For the "PBS NewsHour," I'm John Yang.