Mass Psychogenic Illness

Mass psychogenic illness, also called mass hysteria or epidemic hysteria, is the rapid spread of physical symptoms through a group of people with no infectious agent or other organic cause responsible for the symptoms. It is marked by a sudden onset and equally quick recovery, by occurring within a socially connected group such as a school or workplace, and by spreading through sight, sound or word of mouth rather than through any physical contagion. Symptoms, commonly including headache, dizziness, nausea and abdominal pain, typically begin with an older or higher-status member of the group before spreading to others, and the condition disproportionately affects children and adolescents, particularly girls and young women, usually resolving within a few days. Historical episodes long attributed to mass hysteria include the dancing plagues recorded in medieval Europe, in which large groups engaged in prolonged, involuntary dancing.