Schoolgirls' Mystery Illness: Mass Hysteria or Environmental Toxin?

A bizarre illness has affected about a dozen students at a western New York high school and is making national news. During the first few months of the school year, the students — all girls except one, and mostly friends — began experiencing involuntary jerks and tics. Sometimes their limbs, neck or face would suddenly spasm; other times they would twitch, grunt or shout. It was strange and troubling behavior, made all the more scary because it had no clear cause.

The students at Le Roy High School, in Le Roy, a small town near Buffalo, were examined by school nurses and private doctors, officials from the Health Department, the Centers for Disease Control and Prevention, and Columbia University. None could find any biological basis for the symptoms. The school was thoroughly checked for mold, lead, carbon monoxide and other environmental contaminants; those tests also came back negative. All the experts came to the same conclusion — one that has not been well received by the afflicted students and their parents.

It has been widely described as a baffling mystery and unexplained puzzle, but for most doctors it's neither unexplained, nor mysterious. In fact, the students in the Le Roy case have all the classic symptoms of a well-known (but widely misunderstood) problem called conversion disorder, in which psychological symptoms are converted into physical conditions. Collectively it is known as mass sociogenic illness, or, more commonly, mass hysteria.

The Le Roy case recently got a big publicity boost from noted environmental activist Erin Brockovich, who believes that the strange behavior may be caused by an industrial cyanide spill in 1970 not far from where the school was built. Connecting cyanide to the current outbreak may be a difficult task; there's little evidence that the chemical can cause the neurological symptoms seen in the students, and in any event it's not clear why the chemical would lay inert for more than 40 years before affecting almost exclusively female teen students in one school. [5 Everyday Things that Are Radioactive]

Sociologist Robert Bartholomew, author of more than two dozen articles on contagious conversion disorder and lead author of the book "The Martians Have Landed: A History of Media-Driven Panics and Hoaxes" (2011, McFarland), rejected Brockovich's suggestion, telling LiveScience.com that conversion disorder is almost certainly the correct diagnosis: "Given the elimination of environmental and organic causes, the social patterning of cases is strongly suggestive of mass hysteria. You have symptoms that are almost exclusively confined to young girls, while their parents and male siblings are unaffected. There is no disease or toxic agent that only affects young girls. If it is exposure to toxic wastes near the school, why haven't teachers and maintenance staff who have been at the school for decades been stricken?"

Many people misunderstand the nature of mass hysteria and assume that victims are making up their symptoms. The complaints are real and verifiable; the victims are not imagining their problems. It is not a joke, nor a hoax. Nor is a diagnosis of mass hysteria merely a default explanation when investigators can't find a cause. In fact, there are several fairly specific diagnostic criteria.

Mass hysteria often begins when individuals under stress convert that stress into physical ills. Co-workers, family and friends may also begin exhibiting the symptoms through contagion. Outbreaks are most common in closed social units (such as schools) and where afflicted individuals are under pressure and routine stress. Mass hysterias tend to afflict girls and women more often than boys and men, probably because the illness spreads through social ties and females tend to have stronger social bonds than males.

Bartholomew is also critical of the response by the New York State Health Department. "Their actions in this case are a textbook example of how not to handle an outbreak of mass psychogenic illness," Bartholomew said. "In initially refusing to render a diagnosis, the department generated so much anxiety that they created a public health issue as residents feared the existence of a mystery illness. With Brockovich involved, and with western New York known for toxic dumpsites, this case is not going away any time soon. And with each new media report questioning the diagnosis, it will create more doubt and suspicion and stoke the fear."

This story was provided by Life's Little Mysteries, a sister site to LiveScience. Follow Life's Little Mysteries on Twitter @llmysteries, then join us on Facebook.

Benjamin Radford is deputy editor of Skeptical Inquirer science magazine and co-wrote an article about mass hysteria published in the Southern Medical Journal. He is author of "Scientific