Smartphone technology can already diagnose HIV and syphilis, perform eye exams, and enable mobile ultrasounds and heart monitoring. Now it can also be used to help treat diseases like river blindness and elephantiasis at a fraction of the cost of conventional techniques.
A team at the University of California Berkeley is developing a smartphone-based video microscope—the CellScope Loa—which can identify the telltale "wriggling" motion of parasitic worms in a blood sample. The device—a 3-D printed base for standard smartphones—counts Loa loa worms that complicate the treatment of the diseases.
People get onchocerciasis, or river blindness, after being bitten by black flies. Elephantiasis is spread by mosquitos. Both diseases can be treated with an anti-parasitic drug called ivermectin, but if patients also carry loa loa, the treatment can have dangerous side-effects and people can even die. Hence the need for the Cellscope Loa, which allows health workers to make a decision about whether to use IVM without sending samples back to a lab.
"After the diagnostic completes, the device displays the number of microfilaria detected per milliliter of blood. Based on this number, the device also displays a large, colored indicator reflecting treatment risk based on pre-assessed cutoffs," says Michael D’Ambrosio, a UC Berkeley research scientist.
The Cellscope team, based at the Fletcher Lab at Berkeley, has already completed one 16,000 person trial in Cameroon and is now about to begin a pilot for 40,000 people in the same country. River blindness and elephantiasis are common in West Africa as well as in parts of Asia.
"Current technologies are not compatible with [mass drug administration] campaigns in terms of time and expertise required or cost. The disposable cost of a diagnostic with the CellScope Loa is less than $1 per test, unsubsidized," D’Ambrosio says.
"By combining the low cost and robustness of microscopy with the precision and power of new algorithms, we hope to increase access to medical diagnostics in under-served areas."