How many other studies have been done to investigate the possible association between autism and the MMR vaccination?
There have been several population-based published studies, including this one, to investigate the possible association between autism and MMR vaccination. They have been conducted in countries around the world including England, Sweden, Denmark, and the U.S. The weight of the evidence from these studies does not support an association between the MMR vaccine, or vaccines of any kind, and autism. There have been two laboratory studies suggesting a possible connection between MMR vaccination and autism. These studies have raised the question of whether the MMR vaccine could have caused a persistent measles virus infection of the intestines resulting in a unique syndrome of regression in development and gastrointestinal disorders in some children with autism. The study, however, was not able to distinguish if the intestinal infection was from a vaccine virus or from naturally occurring measles virus. The mechanism of how an infection of the intestine could lead to brain damage resulting
