12/14/2012 05:26 pm ET Updated Dec 14, 2012

Mass Shooting Trauma Survivors Can Suffer From PTSD, Guilt

Parents walk away from the Sandy Hook Elementary School with their children following a shooting at the school, Friday, Dec.
Parents walk away from the Sandy Hook Elementary School with their children following a shooting at the school, Friday, Dec. 14, 2012 in Newtown, Conn. A man opened fire inside the Connecticut elementary school where his mother worked Friday, killing 26 people, including 18 children, and forcing students to cower in classrooms and then flee with the help of teachers and police. (AP Photo/The Journal News, Frank Becerra Jr.) MANDATORY CREDIT, NYC OUT, NO SALES, TV OUT, NEWSDAY OUT; MAGS OUT

Survivors who have witnessed horrible tragedies, such as Friday's mass shooting at Sandy Hook Elementary School in Newtown, Conn., may suffer psychological trauma that may linger long after any physical wounds have healed.

According to CNN, after these types of incidents, counselors often focus on two stages of recovery: the immediate response of helping people feel safe and the longer-term process of helping them cope.

Most people eventually heal, CNN reports, but between 8 percent and 15 percent are likely to develop post-traumatic stress disorder, according to Russell T. Jones, a professor of psychology at Virginia Tech who counseled survivors of that mass shooting.

According to Boston Children's Hospital, post-traumatic stress disorder, or PTSD, is a mental health disorder that can affect children, adolescents and adults who have survived a traumatic experience or series of traumatic events.

Children with PTSD typically experience three types of symptoms: re-experiencing the trauma, avoidance and increased agitation.

Children ages 5 to 12 with PTSD may not have flashbacks or problems remembering parts of the trauma, the way adults experience the disorder. Instead, they may show signs in their play, according to the National Center for PTSD.

They might keep repeating a part of the trauma. These games do not make their worry and distress go away. For example, a child might always want to play shooting games after he sees a school shooting. Children may also fit parts of the trauma into their daily lives. For example, a child might carry a gun to school after seeing a school shooting.

Dr. Melissa Brymer, director of terrorism and disaster programs with the National Center for Child Traumatic Stress, has studied incidents of post-traumatic stress disorder after school shootings in Southern California in 2001 and at Virginia Tech in 2007, according to NBC.

Brymer told the network that anxiety, stress, sleeplessness and even guilt following a traumatic event is normal and even expected. She added that rumors about the incident can exacerbate the situation.

“Not everyone who has been through a school shooting will get PTSD,” Brymer said. “It’s the kids who were directly exposed who are more at risk.”

Pediatric News notes that mental health screenings should be conducted after a school shooting to identify at-risk students and help identify treatment plans.

A study from a shooting at Santana High School in Santee, Calif., showed close to one-fourth of the 247 students directly exposed suffered from PTSD or partial PTSD eight to nine months after incident, according to Pediatric News.

Among all 1,160 students screened, 4.9 precent met criteria for PTSD, and 12.5 percent met partial criteria for PTSD. Depression was present in 15.4 percent of all students and 18.7 percent of those with direct exposure.

Learn how you can help those in Newtown, Conn.