Mass psychogenic illness is when groups of people (such as a class in a school or workers in an office) start feeling sick at the same time even though there is no physical or environmental reason for them to be sick.
Mass psychogenic illness has occurred for hundreds of years, all around the world and in many different social settings. No one keeps track of these outbreaks, but they are probably a lot more common than we realize.
Many outbreaks of mass psychogenic illness start with an environmental "trigger." The environmental trigger can be a bad smell, a suspicious-looking substance or something else that makes people in a group believe they have been exposed to a germ or a poison.
When an environmental trigger makes a group of people believe they might have been exposed to something dangerous, many of them may begin to experience signs of sickness at the same time. They might experience headache, dizziness, faintness, weakness or a choking feeling. In some cases, one person gets sick and then other people in the group also start feeling sick.
Think of how "stage fright" can cause nausea, shortness of breath, headache, dizziness, a racing heart, a stomachache or diarrhea. Your body can have a similar strong reaction to other stressful situations. Outbreaks of mass psychogenic illness show us how stress and other people's feelings and behavior can affect the way we feel. People who feel sick in an outbreak of mass psychogenic illness really believe it is possible that they have been exposed to something harmful.
An outbreak of mass psychogenic illness is a time of anxiety and worry. During an outbreak, a lot of media coverage and the presence of ambulances or emergency workers can make you and other people feel more anxious and at risk. At such a time, if you hear about someone getting sick or if you see someone get sick, it can be enough to make you feel sick too.
No, it doesn't. People who are involved in these outbreaks have real signs of sickness that are not imagined. They really do have headaches, or they really do feel dizzy. But in cases of mass psychogenic illness, these symptoms are not caused by a poison or a germ. The symptoms are caused by stress and anxiety, or by your belief that you have been exposed to something harmful.
Psychogenic illness can affect normal, healthy people. Just because you reacted this way to the threat of something dangerous does not mean there is something wrong with your mind.
The following might indicate that a group sickness is caused by mass psychogenic illness:
The patterns of the outbreak (for example, the kinds of illnesses that are reported, the kinds of people who are affected, the way the illness spreads) might also give evidence of mass psychogenic illness.
However, if any of the following symptoms are true, you should see your doctor to be checked for a different reason for your health problem:
Most of these outbreaks stop when people get away from the place where the illness started. The signs of illness tend to go away once people are examined and doctors find that they do not have a dangerous illness. It is important to keep the people who feel sick away from the commotion and stress of the outbreak.
After experts check out the place where the outbreak started, they can tell people whether it is safe to go back to that place.
Mass Psychogenic Illness: Role of the Individual Physician by TF Jones, MD (American Family Physician December 15, 2000, http://www.aafp.org/afp/20001215/2649.html)
Written by familydoctor.org editorial staff