A non-invasive laser scanner has been used to detect very low levels of malaria infection through the skin of a person. The transdermal scanner is able to detect a single malaria-infected cell among a million normal cells.
The technology developed at Rice University uses a low-power laser to create a tiny vapor nanobubble inside the malaria-infected cell. The bubble bursts and gives out a unique acoustic signal used to make the diagnosis.
The sensor is actually detecting hemozoin, a nanoparticle produced by a malaria parasite inside red blood cell. Regular blood cells do not have hemozoin crystals.
“Ours is the first through-the-skin method that’s been shown to rapidly and accurately detect malaria in seconds without the use of blood sampling or reagents,” said lead investigator Dmitri Lapotko, a Rice scientist.
The device, supported by a low-cost battery, can be operated by non-medical personnel and should be able to screen up to 200,000 people per year at a cost of 50 cents per diagnosis.
While there are other inexpensive tests for malaria, the blood smear is considered the most reliable, but requires a laboratory technician and setup to get a diagnosis. This limits their use in low-resource hospitals and clinics in the developing world.
According to the World Health Organization, in 2012 there were about 207 million cases of malaria and an estimated 627,000 deaths.
[Rice University] [WHO]