Why the H1N1 Vaccine Increased Narcolepsy Rates
A new study suggests genetics may be responsible for the link between the H1N1 and narcolepsy, the Washington Post reported.
According to the World Health Organization, some people have a gene that increases the risk for the sleep disorder, which causes people to suddenly fall asleep. Those who had this gene and received the the Pandemrix H1N1 vaccine made by GlaxoSmithKline were nine times more likely to develop narcolepsy than those who did not get vaccinated.
Following the swine flu pandemic in 2009, narcolepsy cases have been reported in 12 countries, particularly among adolescents ages 5-15. Sweden and Finland reported the highest number of cases.
“The National Institute considers it probable that the Pandemrix vaccine was a contributing factor to this observed increase, and has called for further investigation of other co-factors that may be associated with the increased risk,” the WHO said. “They consider it most likely that the Pandemrix vaccine increased the risk of narcolepsy in a joint effect in those genetically disposed with some other, still unknown, genetic and/or environmental factor.”