Speaker and planning committee member Gary Slutkin of the University of Illinois at Chicago defined infectious disease transmission as occurring when an individual or population is exposed to the particular disease and has an increased likelihood of developing the disease. An individual who is inflicted with a disease exhibits some form of symptoms, which vary depending on the disease. Dr. Slutkin suggested that a symptom of violence can be physically injuring another person; speaker Madelyn Gould of Columbia University added that self-directed injury also can be a symptom of violence. Many workshop speakers noted that violence can be transmitted through either direct victimization or merely through witnessing violence.
The incubation period from when the exposure occurs and until disease symptoms develop can vary. As Forum co-chair Mark Rosenberg of the Task Force for Global Health stated, “it can be a long time between something first affecting a person and when it shows up, so [for example] within a family, children [who are] exposed at a very young age may have its impact much later.” To highlight the similarity between varying incubation periods of violence and other infectious diseases, Dr. Slutkin made a comparison between a young child’s exposure to tuberculosis and child abuse. In cases of tuberculosis, reactivation of the disease can occur when the child is in his or her teens or twenties, just as someone exposed to child abuse may become a perpetrator of dating violence or intimate partner violence during adolescence or later in life.
Several workshop speakers pointed to research showing that violence manifests and spreads as different syndromes—collective, interpersonal, and self-directed—and transmission can result in an infection of the same type of violence to which an individual was exposed or as a different syndrome.
Transmission Within Types of Violence
Dr. Slutkin cited evidence that exposure to community violence can lead to perpetration of community violence (Kelly, 2010). The 2011 London riots are an example of how community violence can quickly spread. Furthermore, large-scale political violence can spread to additional perpetration of political violence, as were the cases in World War II and the mass killings in Rwanda in the 1990s, which Dr. Slutkin cited as examples.
Like the spread of acts of collective violence, evidence shows that exposure to interpersonal violence leads to additional acts of interpersonal violence. Speaker and planning committee member Charlotte Watts of the London School of Hygiene and Tropical Medicine noted that there is