Treatment for both is also similar. The idea is to keep small inflections -- in this case, trivial fights on the street -- from blowing up into deadly viruses. A spat can quickly escalate into a gunfight, as others in the neighborhood feed on the aggressive energy and sometimes look for reasons to pull the trigger.
When two teenage girls got into a fight over a boy on the South Side of Chicago, it caught the attention of local gang members -- with their weapons. Dozens joined the fight. One of the girls was maced.
CeaseFire brought both families together in the group's office in Englewood, Ill. to talk it out. If left untreated, they knew this incident could boil over into bloodshed.
"If something happens to somebody's family, it's going to bring grown folks into it," said Michelob Williams, who is the father of the injured girl. "When grown folks come in there, it's gon' get big time. It's gon' be some real shooting, some real gang banging, and we got enough people locked up."
Interrupter Janell Sails pleaded with the families, "I'm begging y'all, and I don't even know y'all. Please leave it alone."
Both girls eventually agreed to let the issue go, but CeaseFire continues to keep an eye on the situation to make sure tensions don't flare up again.
"If it ain't resolved today, we're gonna keep working it until it get resolved," interrupter Ricardo "Kobe" Williams said.
CeaseFire interrupters also take their work to hospital bedsides to talk with shooting and stabbing victims, knowing that the victims or their friends might seek revenge on the streets. Dr. Salzman explained how intervening at the hospital can be very influential in preventing violence.
"This is the moment where people are most vulnerable. This is the moment of truth, where you can make that change," he said.
Such was the case with gunshot victim Jerrod Spruiel after CeaseFire member Charles Mack paid him a visit in the hospital during his recovery.
"I want to change my life. I'm tired. I'm 24 years old. I feel like I'm 56 years old," Spruiel said.
The group's efforts appear to be having a positive effect in Chicago.
A study funded by the Department of Justice found violence was tapering off in neighborhoods where CeaseFire was active.
"The average effect is between 40 and 70 percent drops in shootings and killings," Slutkin said. "Maywood, just outside of Chicago has gone a year without a single killing and they used to have 20."