RIO DE JANEIRO (AP) — The homicide rate for Brazilian young people under age 19 shot up 346 percent over the past three decades, according to research published Wednesday by the Latin American School of Social Sciences.

During that period, youths became a far higher percentage of Brazil’s murder victims — rising from 11 percent of the total in 1980 to 43 percent in 2010, the report said. The homicide rate for young people rose from 3.1 per 100,000 people younger than 19 years old to 13.8 per 100,000.

This means deadly violence against the most vulnerable members of Brazilian society has surpassed the 10 deaths per 100,000 that mark the accepted threshold of an epidemic, said Julio Jacobo Waiselfisz, a researcher also affiliated with the Brazilian Center for Latin American Studies.

A country’s homicide rate conveys much more than just the number of people who have died, Waiselfisz said.

“Homicide is not a casual act. There is a culture of violence that is leading to the solving of conflicts by exterminating the bothersome element,” he said.

Waiselfisz said part of the increase in youth homicides might be due to the improvement in Brazil’s record keeping in recent decades.

But, he added, it is undeniable Brazil is experiencing an epidemic of violence against young people. Unlike a disease epidemic, however, the violence is not contained or short-lived because it has become part of society, built into relationships, he said.

“There is a discourse that blames the victims, that says these kids are dying because they are doing drugs, or they got into trouble,” Waiselfisz said. “There is a process of institutional omission when faced with these facts, which are taken as natural.”

The numbers in Waiselfisz’s study rank Brazil as the fourth-worst among 91 countries when it comes to youth homicides, behind El Salvador, Venezuela and Trinidad and Tobago.

Perla Ribeiro, head of the nonprofit Association of Centers for the Defense of Children and Adolescents, called the study shocking, and said she hoped that Brazilians will face up to this reality and bring some change.