Mass hysteria

phenomenon that transmits collective illusions of threats, whether real or imaginary, through a population in society as a result of rumors and fear

Mass hysteria or mass psychological illness is a phenomenon when a large group of people share a common emotion. This emotion can be positive, such as people being euphoric at a rock concert, or it can be negative, like after a great person or statesman died. It was first used by the Quarteerly Christian Spectator in 1830, to describe an outbreak of cholera.[1]

Dancing plagues of the Middle Ages are thought to have been caused by mass hysteria


  1. The Journal of Health Conducted by an Association of Physicians (1831) p. 180