A doctor disinfects a Peruvian boy's ear before beginning surgery to remove a cyst at an Expeditionary Medical Support mobile field hospital in Huancavelica, Peru, July 2, 2012, during New Horizons 2012. New Horizons is a U.S. Southern Command-sponsored annual series of joint humanitarian assistance exercises deploying U.S. military engineers, veterinarians, medics and other professions to Central and South American nations for training, construction projects and to provide humanitarian and medical services. (U.S. Air Force photo by Staff Sgt. Michael C. Zimmerman/Released)