in 1976, a national influenza campaign was designed to immunize nearly the entire United States population in fear of an influenza pandemic. However, the A/New Jersey/1976/H1N1 vaccine, also known as the "swine flu" vaccine, was found to be linked with the development of Guillain-Barré syndrome (GBS) and the program ended. This study was conducted to find the relationship between the vaccine and GBS effects.
In 2004 investigators at CDC collaborated with the department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, and the Department of Microbiology, National University of Ireland, Galway, to investigate anti-ganglioside antibody induction by swine flu and other influenza vaccines.