iPhone Camera as Mobile Microscope Yields Modest Accuracy in Worm Diagnosis

According to a study published today in the American Journal of Tropical Medicine and Hygiene by Isaac I. Bogoch, MD, from the Divisions of Internal Medicine and Infectious Diseases at Toronto General Hospital, says the iPhone camera modified as a microscope can yield modest results in detecting worms based on their field study:

The researchers mounted a 3-mm ball lens to the camera of an iPhone 4S (Apple) with double-sided tape. They punctured a small hole in the tape and centered the lens over the telephone camera lens. They placed smear slides of stool samples close to the tape, so that less than 1 mm of space separated the slide and lens. The lens captured the stool sample from atop the slide, which was illuminated from below (estimated equivalence of 50 – 60× magnification). A cellophane strip over the stool prevented lens contamination.

Ht 130311 mobile phone microscopy 250x188

Researchers conducted tests of 199 smears using both their iPhone microscope and conventional microscope. The former was able to capture a “sensitivity of 69.4% and a specificity of 61.5% in detecting helminth infections compared with light microscopy,” with detection at 81% for all Ascaris lumbricoides, a helminth (parasitic worm) species. When it came to detecting hookworms, the impromptu iPhone microscope only detected 14.3% compared to light microscopes, concluding nothing beats the microscope in the field.

“Compared with conventional light microscopy, our simple mobile phone microscope achieved only modest diagnostic yield,” the researchers write. “However, we feel that the mobile phone microscope holds promise as a novel point-of-care test for intestinal helminth diagnosis, because it is portable, easy to construct and use, and relatively inexpensive. More importantly, mobile phones have become ubiquitous worldwide.”

The experiment with the iPhone camera modified as a microscope took place as part of a clinical trial on the safety and efficacy of drugs against parasitic worm infections in school children on Pemba Island, Tanzania. Researchers noted when mobile camera sensitivities exceed 80% in future tests, the smartphone would be worthy of clinical use in the field.

Want to have some fun? You can try this DIY hack to turn your iPhone into a similar microscope.