The Apple store in Santa Monica, Calif., is seen Thursday, May 9, 2013. (AP Photo/Reed Saxon)

By attaching an $8 lens to his iPhone with a piece of double-sided tape, Canadian doctors produced a field microscope that can be used to diagnose intestinal worms in low resource settings, according to a description of the device found in a recent edition of The American Journal of Tropical Medicine and Hygiene.

Dr. Isaac Bogoch, an infectious disease specialist at Toronto General Hospital who led the project, tested his device on 200 stool samples from children who had a mix of hookworms, roundworms and giant roundworms.

Bogoch's iPhone microscope accurately detected giant roundworm eggs 81 percent of the time and roundworm eggs 54 percent of the time. But it was only 14 percent accurate at finding hookworm eggs, according to a New York Times report. Bogoch explained to the Times that hookworms are harder to detect because they rapidly disintegrate outside the body.

To be useful for field surveys, to decide whether to treat a whole village with worming medicine, a device would have to be 80 percent accurate, according to Bogoch. While this version isn't quite there, the fact that smartphone cameras are improving rapidly gives Bogoch hope that it may soon be possible.

Intestinal worms are estimated to affect up to 2 billion people around the world, mainly in poor areas, according to the BBC. "These parasitic infections cause malnutrition, stunted growth and stunted mental development," Bogoch told the BBC. "It's a big deal, a big problem."