After further investigation, researchers at Stanford University are questioning a previously believed connection between H1N1 vaccine and narcolepsy. According to an article in ScienceMag.org by Emily Underwood, the connection theory emerged in 2009 when a small percentage of children in Europe who received the flu vaccine Pandemrix developed narcolepsy.
Last week, that promising explanation “was dealt a setback when prominent sleep scientist Emmanuel Mignot of Stanford University in Palo Alto, California, and colleagues retracted their influential study reporting a potential link between the H1N1 virus used to make the vaccine and narcolepsy.”
Some researchers were taken aback. “This was one of the most important pieces of work on narcolepsy that has come out,” says neuroimmunologist Lawrence Steinman, a close friend and colleague of Mignot’s, who is also at Stanford. The retraction, announced in Science Translational Medicine (STM), “really caught me by surprise,” he says in ScienceMag.org. Others say that journal editors should have detected problems with the study’s methodology.
The work provided the first substantiation of an autoimmune mechanism for narcolepsy, which could explain the Pandemrix side effect, researchers say. “The vaccine, used only in Europe, seems to have triggered the disease in roughly one out of 15,000 children who received it,” writes Underwood. “The affected children carried a gene variant for a particular human leukocyte antigen (HLA) type—a molecule that presents foreign proteins to immune cells—considered necessary for developing narcolepsy.”
Had Mignot’s results held, “they could have led to the first proven example of a vaccine triggering an autoimmune response by mimicking the body’s own proteins,” says vaccinologist Hanna Nohynek, who is working with Vaarala at THL. The retraction “sets us back to kind of a zero point.”