in 1980, the world collectively shed not a single tear upon hearing
that the scourge of smallpox would likely never take another life. A
gargantuan global effort had eradicated the disease in the open (though
the virus still survives in government labs). Now it looks as if
humanity will be able to close the book on polio, another terrible
infectious disease that has wreaked havoc throughout history.
One among the many maladies that remain and take a huge yearly human
toll is malaria, a preventable and curable disease that nonetheless
remains entrenched in 97 countries, where transmission is often rampant.
It’s caused by a handful of species of protozoa in the genus
Plasmodium, whose complex life cycle makes them hard to control. That
cycle involves infecting mosquitos that then bite humans and slip it
into their bloodstream. These humans become reservoirs of the parasite,
and pass the infection back to uninfected mosquitos that bite the
carrier.
According to the World Health Organization (WHO), around 3.3 billion
people are at risk of contracting malaria — just under half of the
world’s population. In 2013, there were nearly 200 million cases of the
disease globally, and it caused around 584,000 deaths. Ninety percent of
cases occurred in Africa, where the disease is endemic in large areas.
But things are looking up in the fight. The WHO reported that the
rate of new cases has fallen by 37 percent and death rates have
decreased by 60 percent since 2000, thanks to improvements in
prevention, diagnosis, treatment and surveillance. “Based on the
progress I’m seeing in the lab and on the ground, I believe we’re now in
a position to eradicate malaria — that is, wipe it out completely in
every country — within a generation,” Bill Gates wrote late last year.
His organization, the Bill & Melinda Gates Foundation, is working
toward that goal by boosting its malaria program budget by 30 percent.
“This is one of the greatest opportunities the global health world has
ever had,” Gates wrote.
But a major hurdle to eliminating the disease resides in one of the
peculiarities of malaria infection. Since the single vaccine available
confers only partial protection in small children, a person not
consistently taking anti-malarial medication must be diagnosed with the
disease before being treated. A number of studies have shown that many
people who live where malaria is present — up to 60 percent of some
sample populations — actually carry the parasite without showing
symptoms. These so-called asymptomatic carriers act as disease
reservoirs, allowing malaria to circulate.
The trouble is that finding the disease in asymptomatic patients
requires serious scientific firepower. To get anywhere near finding most
hidden cases, trained scientists and technicians need expensive and
complicated tools called thermal cyclers, which help them recognize
whether Plasmodium’s genetic material is present in a person’s
bloodstream.
But that type of talent and hardware isn’t necessarily available close
to patients in malaria-endemic regions of Africa, South Asia and Central
and South America. As a result, the process often takes days.
But that’s about to change. GE has partnered up with Global Good,
itself a collaboration between the Gates Foundation and Intellectual
Ventures. The two organizations are developing a new paper-based test
called a lateral flow assay (LFA), which uses a patient’s blood sample
to detect malaria in asymptomatic carriers. When it’s released, the test
will be more powerful than existing LFAs, and similarly affordable and
user-friendly. “We’re operating under the idea that if you can find
those asymptomatic malaria carriers and treat them, then you could
eliminate the disease from a region,” says David Moore, the laboratory
manager of membrane and separation technologies at GE’s Global Research
Center.
In addition to the still-under-development paper-based test, the
partners are also collaborating on an electronic test reader that will
be backpack-portable and battery-operated.
Like a pregnancy test from a pharmacy, the malaria LFA is designed to
identify proteins made by the parasite that are present in the blood,
and provides results within minutes. A positive result is indicated by a
color change on the bioactive paper. The clinician or technician
performing the test will then further analyze the result by the
electronic reader to obtain even more sensitive and accurate results.
“Today, existing solutions tackle diagnosis in symptomatic patients,
albeit sometimes inadequately, but miss infection in asymptomatic
patients, resulting in the cycle of infection continuing,” wrote Matt
Misner, a materials scientist and project leader working in Moore’s lab.
“We expect that the combination of these technologies will stack up to
provide the performance necessary to make a real impact on the way
malaria is treated. Additionally, when successful, we plan to adapt this
diagnostics platform to target other infectious diseases that persist
around the world.”
Says GE’s Moore: “Overall, we’re very pleased with the way things are
progressing. So far, the results are promising and we’re encouraged by
the data we’re getting back.”
This post originally appeared on GE Reports.
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