New tool against vaccines. The study that altered data on patient history and sparked a wave of panic about vaccines that continues today has received new scientific evidence: a large-scale Danish study looks for connections between autism and the MMR vaccine has not found any link between the two, once again.
The furore surrounding vaccines and their link to autism has been looming over us for decades. An article published in 1998 first described a link between the measles, mumps, and rubella vaccine and autism. Both the findings and the principal investigators were completely discredited. The author of the study that sparked the storm, Andrew Wakefield , was stripped of his clinical and academic credentials.
Because of their study – which caused panic – vaccination rates fell and even today have not returned to the levels necessary to adequately protect children against diseases. And it is that scary stories are difficult to forget and worryingly easy to perpetuate.
Override all arguments
Some people have criticized previous studies that found no link between the MMR vaccine and autism. They argue that while the vaccine might not increase the risk of autism globally, it could make a difference in children who are already at higher risk for autism. Another common argument is that the vaccine is “associated with a regressive form of autism, leading to clustering of cases beginning shortly after MMR vaccination.”
The team of scientists set out to overturn these arguments. The findings have been published in the Annals of Internal Medicine.
The researchers, from the Statens Serum Institut in Copenhagen, Denmark, took data from a Danish population registry. In total, they had access to data from 657,461 children; of these, 6,517 received a diagnosis of autism during the 10-year follow-up.
The data
The researchers compared autism rates in children who had received the MMR vaccine and compared them with children who had not. As expected, there was no increased risk associated with vaccination . Similarly, even in children at increased risk of developing autism, this vaccine made no difference.
The risk factors for autism examined by the scientists were: having a sibling diagnosed with autism, low birth weight, maternal and paternal age, and smoking during pregnancy.
In additional analyzes, they also looked for links between different vaccines other than MMR and autism; again, they found none.
One of the main strengths of the study is the large number of individuals included in the analysis. As the authors write, the size of the study allowed them to conclude that “minimal increases in the risk of autism are unlikely to occur after MMR vaccination.”
Looking at the future
“Even in the face of substantial and growing evidence against a MMR-autism association, discussion of the possible link has contributed to vaccine vacillation,” the experts comment with some frustration.
Reference: Measles, Mumps, Rubella Vaccination and Autism: A Nationwide Cohort Study Anders Hviid, MedSci; Jørgen Vinsløv Hansen,; Morten Frisch, MedSci; Mads Melbye. Annals of Internal Medicine 2019 DOI: 10.7326 / M18-2101
