EMELINE WUILBERCQ OKELLO Aballa Ognum regularly has to walk deep into the jungles of southwest Ethiopia to treat the water ponds that harbour a debilitating parasitic disease. Painstakingly, he measures the water volume to determine how much chemical treatment to use against copepods, the tiny water fleas that carry the Guinea worm larvae. If ingested by humans, the larvae can grow up to a meter long before emerging through the skin, leading to serious disability and amputation in the worst cases. Killing them is only part of Okello's job - he also teaches the community about the dangers of drinking…