Who, What, Why: Can a 'ripple effect' cause mass fainting?

Up to 40 school pupils have reportedly fallen ill simultaneously, with several fainting, in what's been described as a "ripple effect". But what might that be, asks Justin Parkinson.

The National Health Service lists several reasons for fainting, which is caused by a temporary reduction in blood flow to the brain.

These include a malfunction in the nervous system, which can be caused by an "external trigger" such as an unpleasant sight or heat. Low blood pressure is another cause, possibly from dehydration, as are heart problems, prolonged standing or emotional stress.

But can these or any other medical theories explain why several pupils at Outwood Academy in Ripon, North Yorkshire, reportedly collapsed at roughly the same time during a Remembrance Day service?

No hazardous substances or gases were detected on the premises. A fire officer has said the room the children were in was hot and that, when a few children fainted, a "ripple effect" caused others to do so. One pupil has described a "domino effect".

One factor might have been a subconscious desire to be "one of the group", says Mark Hamilton, a GP from Manchester. "There's a sense almost of embarrassment if you don't fit in", even when it comes to ostensibly unpleasant activities, he adds. "It's the same sort of principle a hypnotist would use when dealing with a group, getting everyone to do the same. We're more comfortable in groups."

There have been other cases apparently similar to what's been reported in Ripon. In 1965 an "epidemic of over-breathing" occurred in Blackburn, Lancashire, with 85 girls admitted to hospital with symptoms including fainting and dizziness. Anxiety, viruses, food poisoning and a gas leak were suspected as causes, but nothing was proved. Another suggestion was "mass hysteria" relating to a recent polio outbreak in the town.

Earlier this year almost 200 female garment workers in Cambodia were hospitalised after fainting in two separate factories. Poor working conditions, including fumes, were blamed, but the government played down the idea. Thirty children grabbed their stomachs and fainted during a rehearsal of a school play in the US, an incident attributed to "mass hysteria".

Sandi Mann, senior psychology lecturer at the University of Central Lancashire, thinks the same thing might have happened in Ripon. The Remembrance Day service would have created a "heightened" emotional atmosphere, she says. The first person fainting would have increased anxiety among the group, as its cause was unknown. This, in turn, would have led to a second person to do the same, at which point the "ripple effect" starts. Those with a proneness to fainting would have followed, while others whose physiological response to stress is vomiting might have done that.

"Emotion is very contagious," says Mann, who has written a book on panic attacks.

About four in 10 people are thought to faint during their lifetime. This often occurs for the first time during teenage years and is more likely to affect girls than boys.

But the scale of the Ripon incident perplexes Farrah Sheikh, a GP from Greater Manchester. "Fainting has medical causes," she says. "Sometimes if you get up too quickly or a room's too hot it can happen, but I've never come across anything like this.

"And, as it happened around the time of the two-minute silence at 11:00, the kids hadn't had lunch, so it couldn't have been mass food poisoning. It's very strange."

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