Disaster crisis reactions are mainly physical, emotional, cognitive and behavioral. Post-traumatic stress disorder (PTSD) is a psychological crisis triggered by an unusual threat or catastrophic event. These psychiatric states, which typically occur within days to six months after the trauma, include recurrent reliving of traumatic experiences in the form of flashbacks or nightmares, mental distress when witnessing relics or revisiting old places, and persistent avoidance behavior due to fear. Most patients recover within a year, while a few patients continue for years and become permanently mentally burdened, or in some cases, permanently mentally disabled and unable to live a normal life. So what are the circumstances that can lead to a catastrophic reaction? 1. Traumatic events. Physical or sexual violence, serious injury or near death. 2. Staff exposure to a traumatic event. For example, police and firefighters may eventually have a stress reaction.