Kalakalak village, Unity State, Southern Sudan. Malaria Consortium is treating entire communities for the infectious eye disease trachoma, as part of the Neglected Tropical Disease Control Program. Trachoma is endemic in Unity State. Flies, attracted by cow dung in Sudan's nomadic communities, are the primary cause of the bacterial infection. Left untreated, repeated trachoma infections result in entropion - a painful form of permanent blindness where the eyelid turns inward, causing eyelashes to scratch the cornea. Children are the most susceptible to infection, but the blinding effects are often not felt until adulthood. Photograph: Jenn Warren/Malaria Consortium