When a radio play by Orson Welles, War of the Worlds, was broadcasted in 1938 shortly after the suspension of the Munich agreement, the play allegedly caused panic among listeners, who thought that they were under attack by Martians.Another intriguing case is an episode of a Portuguese TV show called Strawberries with Sugar. In the episode, the characters were infected by a life-threatening virus. After the show, more than three hundred students reported similar symptoms as the ones experienced by the TV show characters such as rashes and difficulty breathing. Some schools even closed. The Portuguese National Institute for Medical Emergency concluded that the virus did not exist in reality and that the symptoms were caused by mass hysteria.
Similarly, on Emirates flight 203 in September 2018, dozens of passengers started to believe they were sick after observing other passengers with flu-like symptoms. As a consequence of the panic, the whole flight was quarantined. In the end only a few passengers had a common cold or the seasonal flu.