On-The-Spot Malaria Detector
(Inside Science TV) -- It starts with a mosquito bite and can end in severe sickness and even death. Malaria claims the lives of more than one million people worldwide each year.
Spotting the disease is the first step toward treating it, but the current way to detect malaria is costly, time consuming and not very accurate.
“The people [who] were examining samples for malaria were having such a hard time getting the right answer. They were only right about half the time,” said Brian Grimberg, a biologist at Case Western Reserve University in Cleveland, Ohio.
Responding to the need for better diagnostics, malaria researchers at Case Western developed a portable malaria detector. The detector is comprised of a laser with magnets on each side. It analyzes blood samples of patients suspected to have the disease. Malaria parasites are full of compacted iron, which they release into the blood when they bite their prey. The magnets and laser are able to detect these telltale iron particles.
“If you can imagine iron filings, if you have it on a piece of paper, and you stick a magnet under it, and they all clump together ... that’s kind of what’s happening on a microscopic level with our device,” said Mark Lewandowski, an undergraduate student at Case Western.
The researchers tested a smaller version of the device in the field and found it was 93 percent accurate at spotting cases of malaria. The traditional method -- using a microscope to examine blood -- was just 49 percent accurate. The new magnetic device costs only nine cents per test, compared to about 50 cents for the traditional test.
“Our system, we tried to make it very cheaply ... we just use magnets [and] a cheap laser,” said Bob Diesler, a physicist at Case Western.
The device is being called the Rapid Assessment of Malaria device or “RAM” for short. The faster test is more sensitive as well: in lab tests, the device was able to detect the malaria-laced iron waste left behind by as few as 17 parasites in one microliter of blood. Current technology can detect about 100 parasites per microliter of blood.
The battery-powered system is easily portable and could screen patients in about 20 seconds, which means a large number of people could be tested even in remote areas.
