In this Aug. 8, 2012 photo, traffickers sell drugs in the Antares slum in Rio de Janeiro, Brazil.
The South American country began experiencing a public health emergency in recent years as demand for crack boomed and open-air "cracolandias," or crack lands, popped up in the sprawling urban centers of Rio and Sao Paulo, with hundreds of users gathering to smoke the drug. The federal government announced in early 2012 that more than $2 billion would be spent to fight the epidemic, with the money spent to train local health care workers, purchase thousands of hospital and shelter beds for emergency treatment, and create transitional centers for recovering users.