The majority of children vaccinated against hepatitis B are not at an increased risk of developing multiple sclerosis (MS), according to a study to be published in the October 8, 2008, online issue of Neurology, the medical journal of the American Academy of Neurology.
The study based in France involved 349 children with MS and 2,941 children without the disease. The children were all under the age of 16. A total of 24.4 percent of the children with MS were vaccinated for hepatitis B in the three years before the study, compared to 27.3 percent for the children without MS.
Although the study found that hepatitis B vaccination does not generally increase the risk of multiple sclerosis, the children with MS were 1.74 times more likely to have received a certain type of hepatitis B vaccine, called Engerix B®. Those children with MS developed symptoms three or more years after the vaccine. The risk was only found for this specific type of hepatitis B vaccine and not found for all vaccines against hepatitis B.
This association cannot be taken as confirmation that the vaccine caused MS. Further studies are needed to determine whether this is a causal relationship.
Source: American Academy of Neurology
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