Mass Psychogenic Illness

This article discusses the tendency of non-exposed individuals to seek medical care following a chemical or biological disaster. Although the medical services need to identify those who need immediate treatment, those presenting with ‘psychogenic illness’ should not be dismissed. They may not be well in psychological terms and require empathy for their legitimate concerns. It is suggested that none of us are immune to this phenomenon.


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Definition of mass psychogenic illness

Mass psychogenic illness is the tendency for non-exposed groups to seek medical care following a disaster or emergency incident. It is sometimes called mass sociogenic illness. More precisely it refers to:

“the rapid spread of illness signs and symptoms affecting members of a cohesive group, originating from a nervous system disturbance involving excitation, loss or alteration of function whereby physical complaints that are exhibited unconsciously have no corresponding organic aetiology” (Bartholomew & Wessely, 2002).

Examples of mass psychogenic illness

Following the Sarin attack in Tokyo in which 12 people were killed, approximately 1000 people who were hospitalised had some toxic symptoms, and over 4000 people sought emergency care believing that they had been poisoned, but showed no signs of exposure (Ohbu et al., 1997).

Similarly, after a radiological contamination incident in Goiania, Brazil in 1987, of the 125,800 people screened only 249 were contaminated (Petterson, 1988).

Who is susceptible to mass psychogenic illness?

A review of reported incidents of mass psychogenic illness found no patterns in terms of the social, psychological or physical characteristics of sufferers, and therefore concluded that no one is immune from what is essentially a behavioural reaction that anyone can show in the right circumstances (Bartholomew & Wessely, 2002).

How does mass psychogenic illness spread?

Crucially, this is a social phenomenon in which two or more people share beliefs about a variety of symptoms for which no aetiology can be found. Individuals experiencing acute, unexplained symptoms attribute their illness to the environmental exposure (M. J. Hall, Norwood, Ursano, Fullerton, & Levinson, 2002).

It is suggested that symptoms are spread in a ‘copycat’ way (Baxter, 2002), and can be further exacerbated by reinforcing information such as the arrival of emergency crews in protective clothing (Hyams, Murphy, & Wessely, 2002) and by the general sights and sounds of an incident (MIller, 1999).

Triaging and mass psychogenic illness

Triaging is defined as the sorting of patients and allocation of treatments according to a system of priorities designed to maximize the number of survivors. In the initial stages of an incident triage it is crucial to reliably identify those individuals who have been exposed and therefore require treatment. However, those presenting with psychogenic illness should not be dismissed.

These individuals have been referred to in the literature as the ‘worried well’ (Knudsen, 2001), but this term has also been criticised for being inaccurate and unhelpful because individuals may have cause to be anxious and, moreover, may not be well in psychological terms (Alexander & Klein, 2003; Pastel, 2001). In this sense the phenomenon should not be perceived as panic, but as action following legitimate concerns (Pastel, 2001).

Responding to mass psychogenic illness

The dismissal of the health concerns of the so-called worried-well may cause an impression by the public of non-caring authorities and may reduce trust in the response process. It may also lead people to report exaggerated symptoms in order to get help (Hadler, 1996). It has been suggested that authorities should offer an empathetic, non-judgemental approach to the phenomenon (Engel, 2001).

The literature also suggests that this phenomenon could pose a significant problem for the authorities and health services if large numbers of individuals present with symptoms following a CBRN-type event. Furthermore, the general level of public malaise, fear and anxiety may remain high for years, exacerbating pre-existing psychiatric disorders and further heightening the risk of mass psychogenic illness (Sandra Prince-Embury & Rooney, 1988; Wessely, Hyams, & Bartholomew, 2001) See this article on Community Recovery.

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