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Summary Article: Hysteria
from Encyclopedia of Disaster Relief

Mass hysteria, or “epidemic hysteria,” is a social psychiatric condition in which physiological symptoms of an illness spread through a community even though there is no physical, organic basis for those symptoms. Outbreaks of mass hysteria generally begin as a small number of members within a community begin to present with either real or perceived signs and symptoms of an illness. As other community members witness people exhibiting these symptoms, they begin to become acutely anxious and fearful until, convinced they are suffering from the same illness as the others, they start to present with the same symptoms. This often-overlooked aspect of disaster management can complicate efforts to inform or educate the public, and can lead sufferers to react to disasters in unpredictable and often dramatic ways, potentially affecting healthcare, risk communication, decision making, and resource allocation.

Diagnosis and Symptoms

Diagnoses of epidemic hysteria are often reached by excluding all possible physical causes for the symptoms. Sufferers generally present with similar vague, transient symptoms after seeing or hearing about them; sudden onset of acute stress, fear, and anxiety; and the lack of a plausible organic explanation for symptoms. They differ significantly from other types of hysteria which, though the result of anxiety and stress, lack the social transmission of sensory-motor symptoms.

The physical symptoms of mass hysteria can be difficult to rationalize and can complicate efforts to respond to public health emergencies of all kinds. In cases of suspected outbreaks of food-borne illness, for example, it is not uncommon for unaffected community members to present with symptoms of food poisoning even if they have not come in contact with the suspected source of the infection. Instead, hearing about or seeing others who are suffering is enough to trigger anxiety and, subsequently, physical symptoms. Similarly, the threat of a pandemic outbreak of H1N1 influenza during the 2009-10 school year contributed to an acute increase in the number of people seeking hospital treatment for the disease, whether they had it or not. The mere suspicion of a case of H1N1 was enough to close entire school districts and send concerned parents streaming into emergency rooms and clinics, rapidly overwhelming their capacity to provide care and forcing public health officials to ask the public to stay home unless acutely and urgently ill.

Mass Media and the Rumor Mill

Instances of mass hysteria such as these can often be traced to inadequate, incorrect, or poorly timed messages about hazards and their associated risks; therefore, the potential for mass hysteria should be considered when crafting messages for the public. Though the media can be an excellent partner in disaster management, media outlets often contribute to a cycle that accelerates and intensifies the public dissemination of information, accurate or otherwise. An illustrative example is the hysteria that led to massive efforts to prepare for the Year 2000 (Y2K) rollover, which the media promised would result in a litany of doomsday scenarios, but ultimately amounted to little more than a large inconvenience for computer programmers. While the Y2K scare did stimulate personal and community preparedness initiatives, it siphoned resources from other areas of disaster preparedness with incalculable effects.

Some studies link increased anxiety and depression to perceived threats from terrorist organizations, going so far as to describe chemical and biological threats as “weapons of mass hysteria” rather than “weapons of mass destruction.” These studies make the argument that the real, long-term effects of a WMD attack would not be to lives and property, but to the psychological health of the community, as evidenced by the Aum Shinrikyo sarin attacks in Japan on March 20, 1995, which resulted in few deaths compared to the flood of healthy and mildly ill people who clogged emergency departments and tied up valuable resources.

Mass media has a powerful effect on the way individuals and organizations construct their perception of an event. Disaster relief specialists are not immune to the effects of mass hysteria within their own organizations, although these effects are usually attributed to “tunnel vision” or “groupthink.” Inaccurate or insufficient information can affect an organization's ability to construct a complete picture of a situation and can influence choices about resource allocation and other priorities. For example, pervasive fear of criminal behavior such as looting and violence made the mobilization of military troops a priority during the 2005 response to Hurricane Katrina. Inundated with media reports of pervasive looting, military forces that could otherwise have supported relief operations by distributing supplies or assisted with search and rescue were ordered to “reestablish law and order” in New Orleans, though subsequent studies show that only 237 arrests were made—a statistical decrease in the pre-disaster crime rate.

Mass hysteria is most appropriately addressed as an information management issue at the macro level, although individual circumstances may demand more local interventions such as temporary increases in public education. Carefully designed public education programs can effectively increase citizen preparedness and resiliency by building an accurate knowledge base that will inform their perception of an event as it unfolds. Public relations and other risk communication specialists must carefully manage the amount, timing, authority, and accuracy of information during all phases of a disaster.

Actionable information can be effective at reducing the overall level of fear and anxiety in a community and, as numerous studies show, once the triggering fear is eliminated, anxiety-driven hysterias often pass.

The lesson for disaster management is that densely woven communication networks within communities contribute not only to the spread of hysteria, but also to efforts to control it, as both source and remedy rely on messages propagating through the community.

See Also:

Community Preparedness, Community Response, Healthcare, Hurricane Katrina (2005), Media, Police Departments, Psychology, Mass, Psychology, Personal, Real-Time Communications, Risk Communications, Risk Perceptions, Terrorism

Further Readings
  • American Psychiatric Association (APA). Diagnostic and Statistical Manual of Mental Disorders,4th ed. Washington, DC: APA, 2000.
  • Asensio, Juan A. and Trunkey, Donald D. Current Therapy of Trauma and Surgical Critical Care. Oxford, UK: Elsevier Mosby, 2008.
  • Canton, Lucien G. Emergency Management: Concepts and Strategies for Effective Programs. Hoboken, NJ: Wiley, 2007.
  • Radford, Benjamin and Robert Bartholomew. “Pokemon Contagion: Photosensitive Epilepsy or Mass Psychogenic Illness?” Southern Medical Journal, v. 94/2 : February 2001.
  • © SAGE Publications, Inc

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