A specialist science college was evacuated yesterday after a film on human biology apparently sparked mass hysteria.

More than 30 pupils, aged from 11 to 13, as well as a teaching assistant were taken to hospital after three children initially told teachers that they were feeling unwell.

As other children, mostly from Year 7, at Royston High School in Barnsley, South Yorkshire, joined the sick list, staff reported a domino effect. When the entire class began feeling faint and nauseous, they called in the emergency services, fearing a gas leak.

All students and staff were assembled in the hall and sports hall before it was decided, on the advice of paramedics, that everyone at the 627-pupil school should be removed.

Eventually 32 pupils were taken by ambulance and patient transfer vehicles to Barnsley District Hospital for check-ups, as emergency services monitored the school. A hospital spokesman said: “The children were brought into our emergency department. We checked their blood pressure, pulse and blood sugar levels. I have never come across anything like this before.”

Two hours after the evacuation the all-clear was given and lessons for the older children unaffected by the scare resumed as normal after the lunch break.

Kay Jenkins, the head teacher, said: “I must emphasise that no children were ever in danger because of the fast, effective, co-ordinated response from the school and the joint emergency services.”

She said that no gas leak had been found and that there were no experiments taking place in the science laboratory at the time. “We are still unsure about what happened, but a group of 30 students were watching a human biology video which is regularly shown in a science class,” she said. “It is about the human body and how it works and no blood is shown on the screen.

“Three children asked to leave and came down to the medical room feeling a bit queasy. Then another couple came down and at that point, as a few pupils were showing similar symptoms. We contacted the ambulance service and on the advice of the emergency services the school was evacuated as a precaution.

“The police and fire services searched the building while the paramedics stayed with us to see it through. We evacuated the school because there was a lot of upset.”

All the children were discharged within four hours of arrival at hospital. Many were picked up by anxious parents.

The incident was the latest of several ascribed to mass hysteria.

Almost 300 children in Holinwell, Nottinghamshire, collapsed and were taken to hospital while competing in a brass band competition in a field in 1980.

But the biggest outbreak was in 1955 when 300 nurses at the Royal Free Hospital in London complained of paralysis.

Psychiatrists wrote a description of events for the British Medical Journal and described it as mass hysteria.

But since then, the history of mass hysteria has become divisive. Some claim it to be all in the mind while others assert that there may yet be an agent, infective or chemical, that could cause such symptoms.

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