On 30 January 1962, a girls’ school in Kashasha, twenty-five miles outside of Bukoba on the coast of Lake Victoria in the state of Tanganyika (present day Tanzania), was suddenly afflicted with a bizarre case of spontaneous laughter. Three girls began laughing and couldn’t stop. Stranger still, the laughter spread throughout the school and eventually into surrounding villages. The laughter lasted on average seven days and sometimes as long as six months. By the time the epidemic ended, 14 schools had to be shut down and 1000 people were infected. What happened?