MMR vaccine that protects children against the measles, mumps and rubella (hence the name MMR) has been an issue of controversy ever since 1998 when a physician Andrew Wakefield linked the vaccine to the autism incidence.

He showed in his study that a live measles virus contained in the vaccine could move to the intestines and remain there causing inflammation eventually resulting in lifelong gastrointestinal problems and neurological damage.

Although many following studies have disputed the link, parents' fears have persisted leading to their refusal to have their children vaccinated against measles, further leading to highest number of cases seen in the United States in a decade, 131 so far this year.

A new study, done by Scientists at Columbia University in New York and the U.S. Centers for Disease Control and Prevention (CDC) in Atlanta may finally put those fears to rest.

They took a different approach and assessed the link with respect to kids with autism and GI complaints. They collected intestinal tissue samples from 25 children with autism who also suffered gastrointestinal (GI) problems and compared them to samples from 13 children of similar ages who had GI problems but no autism.

All the children had been vaccinated at younger ages and were undergoing colonoscopies for GI conditions. The samples were tested for genetic traces of the measles virus using the most modern genetic technology in three laboratories that were not told which came from the children with autism. To check if the vaccinations preceded either their autism or bowel problems, researchers have taken their anamnesis (data about the children's immunization histories and health).

The tests showed traces of the genetic material in the intestines of one boy with autism and one boy without autism and that only five of the 25 autistic children received the MMR vaccine before their GI complaints.
There was no difference in children with GI complaints and no autism and children who had autism and no GI complaints.

The study has, however, only concentrated on the current MMR vaccine that does not contain thimerosal and has not addressed other vaccine-autism theories, such as the fear that the mercury-containing preservative thimerosal might cause autism.

While some experts say these results are definitive, there are others who disagree.

National Autism Association (NAA) for example called the study "flawed" saying that it "fell far short of what the public needs to prove safety of the MMR vaccine."

SafeMinds, an autism-advocacy organization, also believes that the Lipkin study does not close the book on the theory that the MMR vaccine might trigger autism.

They say the study was too small to clear MMR vaccination as a possible factor and that it is premature to discount MMR from a study of this size.
There could be subgroups in which MMR is exacerbating or leading to the gastrointestinal inflammations seen in these children.

Many parents are also not convinced and are calling for more research to discover what vaccines might have done to their children.