Some preliminary data suggest a link between rotavirus vaccine and intussusception.
Intussusception is a rare type of bowel blockage that occurs when a part of the bowel telescopes down into another segment. Sometimes, the bowel blockage self-corrects, but it can also require surgery, and in rare cases lead to death. The number of reported cases is approximately what would be expected based on the natural rate of occurrence of intussusception, regardless of vaccination. However, given that under-reporting of cases occurs in every surveillance system, this information is concerning. In addition, post-licensure studies in Northern California, Minnesota and South Carolina also support a link between rotavirus vaccine and increased risk of intussusception in the first 3 weeks following vaccination.