The 1976 swine flu outbreak, also known as the swine flu fiasco, or the swine flu debacle, was a strain of H1N1 influenza virus that appeared in 1976. Infectious morbidity was only detected from January 19 to February 9, and were not found outside Fort Dix. The outbreak is most remembered for the mass immunization that it prompted in the United States. The strain itself killed one person and hospitalized 13. However, side-effects from the vaccine are thought to have caused five hundred cases of Guillain–Barré syndrome and 25 deaths.