Blackburn Cathedral Fainting Epidemic (1986)

In the summer of 1965, over 300 people in Blackburn, England, began fainting without warning while waiting for Princess Margaret's visit to Blackburn Cathedral. The next day, 98 pupils at St. Hilda's Girls' School experienced similar unexplained fainting. A year later, a report in the British Medical Journal attributed the incidents to mass hysteria or an "epidemic of overbreathing."