Some 2 billion people around the world are affected by parasitic worms. Researchers trying to help them may soon use a simple iPhone hack.
The Toronto General Hospital's Isaac Bogoch and colleagues found that "mobile phone microscopy" has a sensitivity of about 70 percent for detecting the eggs of parasitic worms, also known as helminths.
They pierced a small hole in the tape and placed the ball lens against the hole.
Next, smear slides of stool samples from children in Tanzania were held up against the tape while a flashlight illuminated the slides.
The camera snapped images of the samples and the results were checked for the presence of eggs. The camera could resolve eggs as small as 40-60 micrometers in diameter.
Conventional light microscopy by trained lab technicians was used to study the slides, seen in the image below (slides B and D were shot with the iPhone; A and C were shot with conventional microscopes).
The concept has been tried before at the University of California at Davis.
Bogoch and his collaborators found that the iPhone procedure had a sensitivity of 69.4 percent for detecting any parasitic worm egg and sensitivities of 81.0, 54.4, and 14.3 percent for the diagnosis of Ascaris lumbricoides (a roundworm that can grow up to 12 inches long), Trichuris trichiura (aka whipworm), and hookworm, respectively.
The researchers were seeking a useful diagnostic test, and while the iPhone scope worked as a proof of concept, 70 percent sensitivity wasn't up to scratch.
"However, we feel that the mobile phone microscope holds promise as a novel point-of-care test for intestinal helminth diagnosis," they write, "because it is portable, easy to construct and use, and relatively inexpensive. More importantly, mobile phones have become ubiquitous worldwide.
"Mobile phone diagnostic technology will likely contribute to the diagnosis of infections and non-infectious etiologies in resource-constrained settings."
(Via BBC News)