A strain of influenza A that was traced to its origin in swine in 1976, and caused a small localized outbreak of virulent influenza that killed at least one serviceman in a military camp in the United States. All indications were that this could be the beginning of a very large epidemic, but for whatever reason this did not materialize. The Centers for Disease Control and Prevention was able to rapidly prepare and distribute large quantities of a specific vaccine, and this was given to some 20 million people. About 80 of them subsequently contracted Guillain-Barré syndrome with paraplegia. This was wrongly attributed to the vaccine until it was realized that the number of cases during the period in question was no greater than would be expected by chance. But by the time this was realized the harm had been done, and many people still believe that influenza vaccine carries significant risk of this complication.