Of the neglected tropical diseases, parasitic worms, or helminths, are one of the most common maladies. Diseases like this, caused by parasite or bacteria, kill around 534,000 a year, according to the CDC. These have been largely wiped out in developed countries, but they still persist in the poorest parts of the world. People pick up infections by walking or consuming bits of contaminated soil in areas where sanitation is poor. After a person becomes infected, he perpetuates the infection in others through feces teeming with worm eggs.
Treating the worms is usually straight forward, but doctors must first determine whether or not a person is infected. Microscopes are not always available in poor communities, however, since they are difficult to transport and break easily. To get around this, an international team of doctors have developed an impromptu microscope by sticking a cheap lens onto his iPhone using double-sided tape. The New York Times describes the contraption:
The invention, described recently in The American Journal of Tropical Medicine and Hygiene, was tested in Tanzania on 200 stool samples from children who had a mix of hookworms, roundworms and giant roundworms.
A three-millimeter ball lens was taped over the camera lens of an iPhone 4. The zoom was increased to maximum, and slides, with tape atop the samples, were pressed right up to the lens. A pen flashlight shone light through the slide.
The improvised microscope detected giant roundworm eggs 81 percent of the time, roundworm eggs 54 percent of the time and hookworm eggs 14 percent of the time. The latter parasite may evade detection because it produces fewer eggs which also tend to degrade quickly outside of the body, the Times writes.
In order for doctors to determine whether or not to treat a person or village with anti-helminth medication, they need to have a microscope that performs with at least 80 percent accuracy. Unfortunately, the iPhone scope delivered results at just 70 percent accuracy compared to a conventional microscope. But with increasingly high tech smartphone cameras frequently introduced, the Times points out, the iPhone may soon find its place as a diagnostic tool after all.
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