Dalma Cartagena teaches a class on agricultural science to elementary-school students in Orocovis, Puerto Rico. "I'm preparing them to make good decisions when it comes to the environment and healthy foods," she says.
The posterior end of the Loa loa worm is visible on the left. The disease-causing worm can now be located with a smartphone/microscope hookup. That's a big help because a drug to treat river blindness can be risky if the patient is carrying the worm.
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