Mass hysteria, also known as mass sociogenic illness, is likely responsible for several cases of people falling ill around the world, including incidents last week in a Vietnamese factory and on a British Airways flight forced to make an emergency landing.
According to Vietnamese newspaper "VN Express," 66 female workers at a garment factory in Vietnam's Quang Nam province mysteriously got sick last week: Twenty three workers fainted on Thursday, followed by another 43 the following day. Workers complained that an unexplained odor made them tired and caused difficulty breathing. The workers were briefly hospitalized, but no environmental toxin or underlying cause for the illness could be found -- all were soon released. Though initially attributed to excessive heat, Pham Ngoc Hoa Binh, director of a hospital that treated many of the workers attributed the symptoms to a "case of hysteria."
Earlier that week on Oct. 25 hundreds of passengers were diverted to Vancouver International Airport after a British Airways flight from San Francisco to London made an emergency landing when a mysterious illness sickened some of the flight crew. British Airways issued a statement that 25 crew members were hospitalized as a precaution, though it's not clear how many of them actually became sick or reported symptoms. Another report merely said that "several crew members reported feeling unwell."
The element of social suggestion - or what psychologists call "priming" - is evident in this exchange, as reported by CBC News: "passenger Stefan Orberg wondered if there was something in the air; 'The [flight] attendants asked me, did you feel anything in your eyes? I thought, well, maybe I had.'"
This is common in mass hysteria cases, where the idea that some unseen, unknown - and therefore potentially toxic -environmental contaminant is present is spread from person to person. Because the signs are subtle, even those who do not experience anything out of the ordinary might agree that, yes, now that someone mentions it, maybe they do smell something odd, or are in fact feeling a bit lightheaded. This can cause panic - especially if they are in a place that offers no escape such as an airplane - which then escalates the person's symptoms and helps spread the hysteria.
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If there were indeed some unknown airborne toxin in the British Airways cabin the air conditioning system would quickly spread it passengers throughout the whole plane. There's no reason why only a handful of crew members would be affected - unless the symptoms were self-generated or psychosomatic.
As both of these cases suggest, mass hysteria outbreaks often occur among co-workers, who may begin exhibiting the symptoms through contagion. Mass hysteria is often misunderstood as being an illness that sufferers are making up. In fact the symptoms are verifiable and not imaginary. The issue is instead what is causing the symptoms - whether some external environmental contaminant or instead a form of suggestion-driven social contagion.
Humans are social animals and we often take our cues from other people, both consciously and unconsciously. People can unconsciously mimic the actions and reactions of their peers - that's one reason yawns are contagious. If one or more people start to faint or feel sick in their presence it can create a domino effect, spreading to others.
Symptoms of mass hysteria are typically both minor - shortness of breath, fainting, nausea, and fatigue - and short-lived, lasting anywhere from a few minutes to a few hours. Because there is no physical irritant to treat or remove from the patient, there is no real treatment other than attention from doctors, parents, teachers or other authorities.
Mass hysteria is more common that often recognized, and leaves no lasting harm. In both these cases all those affected have fully recovered, and the only lingering problems are complaints from angry British Airways passengers whose plans were disrupted by the incident.
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