Influenza vaccines were first noted to be associated with Guillain Barre Syndrome during the 1976 swine flu epidemic, when it was found that the risk of getting paralysis from GBS was increased 4 to 8 times for people who took the vaccine. This increased risk lasted for 6 weeks following the vaccination. GBS is an autoimmune disorder in which the nervous system is damaged with resultant tingling, muscle weakness and paralysis. By stimulating the immune system with vaccines to fight future infections, some people end up with an imune system that attacks them by mistake. More modern vaccines have undergone attempts to make them safer. A recent study confirms that GBS still occurs following influenza vaccines with 2 people over the age of 50 developing GBS for every one million people vaccinated.