Who would have thought that a threat to children would be exaggerated by parents, teachers, and the media? “Not I,” he said sarcastically…

BBC News - Warning of nut allergy ‘hysteria’

Measures to protect children with nut allergies are becoming increasingly absurd and hysterical, say experts.

A peanut on the floor of a US school bus recently led to evacuation and decontamination for fear it might have affected the 10-year-old passengers.

Professor Nicolas Christakis, a professor of medical sociology at Harvard Medical School, told the BMJ there was “a gross over-reaction to the magnitude of the threat” posed by food allergies, and particularly nut allergies.

In the US, serious allergic reactions to foods cause just 2,000 of more than 30 million hospitalisations a year and comparatively few deaths - 150 a year from all food allergies combined.

Professor Christakis said the issue was not whether nut allergies existed or whether they could occasionally be serious. Nor was the issue whether reasonable preventative steps should be made for the few children who had documented serious allergies, he argued.

“The issue is what accounts for the extreme responses to nut allergies.”

He said these responses were extreme and had many of the hallmarks of mass psychogenic illness (MPI), previously known as epidemic hysteria.

Often seen occurring in small towns, schools and other institutions, outbreaks of MPI involve healthy people in a flow of anxiety, most often triggered by a fear of contamination.

Being around individuals who are anxious heightens others’ anxiety, leading to a self-perpetuating cycle which can spiral out of control.

(via Bruce Scheier, who links to Virginia Tech and Thai Chili Sauce as other examples of MPI).