A new study has thrown more light on the controversy surrounding the MMR vaccine and whether it causes autism. In a study of 52 autistic children who had the vaccine, 43 of them had antibodies to the vaccine virus, which were not found in any of the healthy controls, including 15 siblings.
The researchers suggest 'autistic children have a hyper-immune response to measles virus, which in the absence of a wild-type measles infection might be a sign of an abnormal immune response to the vaccine strain or virus reactivation.' In other words, the vaccine does not cause autism, but it triggers it in autistic children, who are hypersensitive to it.
Perhaps by blending the research about head and brain development, parents of potentially autistic children may be able to determine if their child should be given the vaccine.
(Source: Autism Research Review International, 2003; 17: 6).
* Researchers have discounted fears, especially among parents in America, that thimerosal in vaccines could cause autism. Thimerosal, which is 50 per cent mercury, is used as a preservative.
The researchers compared autism and vaccination rates in California, Sweden and Denmark, and found that, while autism rates continued to increase in all three regions, vaccines containing thimerosal had been removed in Sweden and Denmark by the early 1990s.
(Source: American Journal of Preventive Medicine, 2003; 25: 101-6).