The homicide rate among youth in Latin America is double or triple the rate in all other parts of the world except Africa, according to the World Health Organization. “It’s a huge problem in Central America,” Richard Jones of Catholic Relief Services said. El Salvador, Guatemala and Honduras, which suffer gang violence, are seeing an increasing impact from drug trafficking. In El Salvador the homicide level in the age group 15 to 20 is 90 per 100,000 young people—nearly five times the rate that W.H.O. considers an “epidemic.” In Brazil the youth homicide rate rose from 41.7 per 100,000 in 1996 to 52.9 in 2008. Homicide rates in Latin America could be affected by the broad availability of guns, but efforts to calculate the impact of such factors as guns and drug trafficking are stymied by a lack of data.