Post-traumatic stress disorder (PTSD) is a mental health disorder than can occur after a person has experienced or witnessed a traumatic event. It causes intense fear, helplessness or horror. It is described in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), published by the American Psychiatric Association. The symptoms of PTSD often surface within three months of the traumatic event that caused it but can also surface years later.
PTSD has become a global health issue and the prevalence of it is gaining awareness. In Canada, between 1.1 and 3.5 per cent of the general population is thought to have PTSD. 
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