If a group of people present real symptoms in the absence of a specific disease or cause, it is called mass psychogenic illness.
Main characteristics of mass psychogenic illness
The definition of this condition is somewhat broad and subjective, since the related terms that are used regularly in psychiatry tend to be different. For example, the most similar entity included in the Diagnostic and Statistical Manual of Mental Disorders (DSM) is “hysterical neurosis.”
According to a publication by the Mayo Clinic, this is part of the DSM-V and fits into functional neurological disorders. This is a set of neurological symptoms that cannot be explained by an “organic” disease. That is, despite medical efforts to find a cause, a psychiatric problem is indicated as the origin of the symptoms.
This does not mean that the clinical manifestations are not real. This is a phenomenon that is still poorly understood, but it is most likely a consequence of the anatomical and functional organization of the nervous system when faced with an intense stressor stimulus. In fact, telling a patient in a crisis that his symptoms are “part of his imagination” could make the problem worse.
In the specific case of the psychogenic disease of the masses, the functional disorder is not suffered by one person, but by many. Any adverse environmental event—news, for example—is capable of triggering symptoms in predisposed people. This is what is most often associated with collective hysteria, which is often underdiagnosed.