In a previous era, spirits and demons oppressed us. Although they have been replaced by our contemporary concern about invisible viruses, chemicals, and toxins, the mechanisms of contagious fear remain the same. The rapid outbreak of illness described by Jones et al., the particular symptoms involved, the unusual odor that triggered the outbreak, and the spread of illness along lines of sight and through social networks are all characteristic features of mass psychogenic illness.3,5 Although the Tennessee case may not be unique, the message that not all such outbreaks have toxic causes bears frequent repetition.6
Eventually, the services and authorities called to the high school in McMinnville emergency medical services, environmental and public health agencies, and so on were convinced of the psychological nature of the episode (and it appears that many thought so from the outset but did not say so). They packed their bags and went home, perhaps with regrets about the enormous cost of the investigations. But it ended happily or did it? There are hints in the report that all was not well after the episode. Some of those affected continued to report symptoms after the outbreak. There were rumors of incompetence and a coverup. This episode may not be over yet.
Indeed, managing the aftermath of such an outbreak may be the greatest challenge. Research has consistently shown that acute, short-term, epidemic anxiety is a common phenomenon that can affect normal people and that is not associated with any major psychological or personality disturbance. It is probably part of the behavioral repertoire in all of us, triggered by the right conditions of fear and uncertainty. If mishandled, however, what should be a transient, harmless phenomenon affecting normal people may become a chronic illness in a smaller number of people.
The difficulty is evident in the title of the report. The term "psychogenic illness" and its predecessor, "mass hysteria," exemplify the problem, both in the meaning of the words themselves and in their interpretation. One of the less welcome aspects of the Freudian tradition has been the widespread acceptance of the existence of symptoms that are, in that destructive phrase, "all in the mind." Yet psychogenic symptoms are physiologic experiences that are based on identifiable physiologic processes that cause pain and suffering.7 The children at McMinnville High School experienced genuine symptoms. That the cause of these symptoms was probably anxiety about toxic exposure, rather than any exposure itself, does not detract from their reality. By labeling the episode psychogenic or hysterical, however, that is precisely what we are doing. To the majority of observers, including most professionals, these symptoms are indeed all in the mind. The compelling intellectual arguments against such crude dualism8,9 have had little effect on the views of laypersons and professionals alike.
When those who have been caught up in episodes similar to the one described by Jones and colleagues learn that others believe the symptoms were not due to a mystery gas after all, they are likely to feel that their credibility is being challenged. The current report may not be well received in McMinnville. In some episodes and let us hope this one is an exception a minority of those affected remain ill. The only way to prove the veracity of their distress, in the face of doubt, disbelief, and stigma, is to continue to experience it not least in order to prove the investigators wrong. As Hadler observed, "If you have to prove you are ill, you can't get well."10
Those in McMinnville face an additional kind of jeopardy. It is possible that they will be caught up in a wider social debate and will become the subject of controversy, media attention, and special-interest advocacy. Their personal experiences may become evidence in a political process.11 It is now commonplace to blame our environment for many of our ills. Episodes such as the one described by Jones et al. can be understood only in the context of widespread fears about the deteriorating quality of our environment and communities. The belief that one is possessed by demons has little resonance nowadays, but the belief that one is the victim of a mystery gas does, in part because of the all-too-frequent accounts of episodes in which such fears were justified. The explanations made by the affected persons in McMinnville make sense when we remember the legacy of Seveso, Bhopal, and Chernobyl.
Given the frequency of mass psychogenic illness, the lack of empirical knowledge about its management and prevention is particularly unfortunate. There are several case studies of how not to manage such episodes, but we rarely, if ever, hear about incidents handled sensitively, with no long-term repercussions involving ill and embittered people and ambitious investigative reporters. Should we investigate at all? Does the deployment of large numbers of emergency, public health, and environmental specialists merely add fuel to the fire, convincing people that there really is something serious going on? Or does public reassurance depend on an exhaustive investigation that rules out every possible external cause, however improbable? How do we convey in a respectful manner the message that the main mechanisms for the transmission of distress are psychosocial and behavioral rather than toxicologic? Should we even try? When symptoms similar to those described by Jones and colleagues and almost certainly with the same cause developed in 34 workers on the Triborough Bridge in New York, their employer was reluctant to endorse the medical conclusion that the symptoms were psychogenic. A spokeswoman for the Triborough Bridge and Tunnel Authority said, "No, I don't think we want to prove it as hysteria. These people work very hard, and we don't want to make light of what happened to them."12
A firm public message that certain symptoms are probably psychological in origin will probably help prevent their spread, but possibly at the cost of alienating those already affected and their families. The challenge is to convey the scientific reality without being seen as blaming or demeaning the victims. At present, we have little information on which to base crucial decisions about managing mass psychogenic illness.
Simon Wessely, M.D.
Guy's, King's, and St. Thomas' School of Medicine
London SE5 8AF, United Kingdom