A new study concludes that a childhood vaccine against measles, mumps, and rubella is not linked to autism, reports the Washington Post. Researchers studied bowel biopsies from 38 autistic children and found no link between the vaccine and the digestive problems often associated with autism. The results, which contradict the findings of an earlier study, come amid a federal investigation on the controversial topic.
One theory suggests that the live measles virus in the MMR shot lingers in the intestine and releases toxins that lead to autism. The new study found traces of the virus in only one autistic child, and found traces in a non-autistic child. A patient advocate praised the study, but said that it "does not exonerate the role of all vaccines."