Today's post, by John Rich, is the first in a series of contributions by members of an expert panel intended to expand the breadth of The Public's Health. Rich, a primary care physician and director of the Center for Nonviolence and Social Justice at Drexel University School of Public Health, discussed his work during a 2010 interview for his book Wrong Place, Wrong Time: Trauma and Violence in the Lives of Young Black Men.

By John A. Rich

In the days since a gunman opened fire on moviegoers in Aurora, Colo., the nation has watched as stories of inexplicable horror and death have emerged alongside stories of miraculous survival and a community coming together to heal. The focus has also turned to the alleged perpetrator of these violent acts, in an attempt to understand or even explain why someone might so randomly attempt to take so many lives. Other reports have looked at the issue of firearms, reasonably asking how someone so unstable could accumulate such an arsenal of lethal weapons.

While many of these topics may seem to be more the stuff of criminal justice, many of the underlying questions relate to public health - specifically, what we know about how catastrophic violence affects the health of everyone.

Research on survivors of man-made disasters has taught us a great deal about who is most likely to suffer the most severe psychological consequences of exposure to violence, specifically post-traumatic stress disorder. Studies estimate that 30-40 percent of those who are directly injured or who were in the line of fire will develop PTSD. Rescue personnel, such as emergency medical technicians who are on the scene in the immediate aftermath, suffer significant though somewhat lower rates, with 10-20 percent developing PTSD. Researchers studying the shooting massacre at Virginia Tech in 2007 found high rates of traumatic symptoms -15.4 percent of students surveyed the following summer had probable PTSD. And those who knew someone who was injured or were unable to confirm that a friend was safe were twice as likely to have PTSD as those who did not.

Surprisingly, research has shown that even those who are not directly affected by any aspect of the violence are also at risk. Sandro Galea, an epidemiologist at Columbia University Mailman School of Public Health who studies trauma in populations around the world, made just this point in a recent lecture at Drexel University's School of Public Health. He and his colleagues have studied residents of New York City in the six months following the 9/11 terrorist attacks. Rates of PTSD were highest among those directly exposed to the attack. The researchers estimated that 28.3 percent of the 13.5 million people in the New York metro area – or 3,820,500 individuals - were directly affected by the attacks and that 12 percent of them developed PTSD. This translates into an estimated 460,000 people with PTSD. By comparison, of the 71.7 percent of those not directly affected – or 9,679,500 people, or 3.7 percent - developed PTSD. Translation: 360,000 of those not directly affected by the attacks developed PTSD, even though their rates were far lower.

So in terms of sheer numbers, there were almost as many cases of post-traumatic stress disorder among people who had no direct exposure to the attacks as there were among those who were directly affected in some way. The message seems clear: our minds and bodies react not only to our own trauma but also to the trauma of others in our communities.

What might this mean for the residents of Aurora, Colo? In the coming weeks and months, mental health support and treatment for PTSD will be needed for more than the victims and rescue personnel. The public health and behavioral health communities must mobilize to meet the mental health needs of residents throughout the area, many of whom will develop PTSD.

What relevance might this hold for Philadelphia or other major cities?

First, man-made acts of violence take their toll on the mental and emotional health of the entire community. As cities prepare for the next unexpected disaster, mental health preparedness is as important as physical or infrastructure preparedness. Philadelphia's Department of Behavioral Health and Intellectual (DBH) disAbility Services has taken a positive step toward the goal of supporting mental wellness through its commitment to training community members in Mental Health First Aid (MHFA). The DBH website explains that "MHFA teaches the skills needed to identify, understand, and respond to signs of behavioral health challenges or crises." Equipping community members to intervene when violence happens can infuse needed healing into neighborhoods where violence is prevalent.

Second, although we do not know as much as we need to know about the health effects and levels of PTSD due to "everyday violence" in Philadelphia, considerable research supports the notion that high levels of violence and trauma affect all of us, emotionally and physically, whether we are directly exposed to the violence or not. Any investment that Philadelphia makes in increasing mental wellness and decreasing violence should add value to the health of all of us.

Finally, Sunday's attack on a Sikh Temple in Oak Creek, Wisc., which took the lives of six people, reminds us that incidents of violence will recur, whether driven by mental illness, racial hatred or grinding poverty. Each tragedy will trigger the residents of Aurora to remember their losses, often in very painful ways. A challenge for the survivors in Aurora, and for us here in Philadelphia, is to resist the temptation toward numbness, and instead to mobilize the "survivor mission" to advocate for effective solutions, like preventive mental health, common sense gun control and healing approaches to traumatized communities.

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