Two years ago, Pakistan’s Punjab province was hit with a deadly dengue fever epidemic. An estimated 20,000 contracted the infectious disease. This year, cases have numbered in the dozens. Many credit a mobile phone-based campaign developed by computer scientist Umar Saif with thwarting another outbreak. More than 67,000 prevention activities were photo-logged and geo-tagged to coordinate the eradication drive. A huge success in a country where few can rely on basic services like electricity.