MONTREAL – Measles found in the intestines of a cohort of autistic children with bowel disease should not be perceived as proof of an association between the measles vaccine and autism, Stephen J. Walker, Ph.D., stressed at the 5th International Meeting for Autism Research.
“We haven't done anything to demonstrate that the measles virus is causing autism or even causing bowel disease. We have simply shown that there is measles virus in the guts of a large number of children who have regressive autism,” said Dr. Walker of Wake Forest University in Winston-Salem, N.C.
A high percentage of children with autism have chronic bowel disease, which can have a direct influence on cognitive and behavioral issues associated with the condition, Dr. Walker said.
To explore the potential causes of autistic enterocolitis, the nonspecific ileocolitis with ileocolonic lymphonodular hyperplasia that plagues many of these children, Dr. Walker and colleagues have so far assayed terminal ileum biopsy tissue from 82 of 275 autistic children who had been referred to a pediatric gastroenterologist for evaluation. Eighty-five percent of the children tested, all of whom have the regressive form of autism in which an apparently normal child loses skills, have tested positive for the measles virus.
In addition, Dr. Walker noted, “of the handful of results we have in so far, all of the measles viruses are vaccine strains and none are wild measles.”
In emphasizing that the findings are preliminary, Dr. Walker noted that “there are lots of viruses in the gut and any one of them could be the cause of chronic inflammation in these kids.” While the findings do not confirm a causative link between the measles component of the measles/mumps/rubella virus suggested by a British scientist in 2002 and causing a maelstrom of accusations and protests, “if the virus from the vaccine is the cause of inflammation and chronic bowel disease in some susceptible children, that is something that needs to be known,” he said.
Because of the long-standing controversy surrounding the MMR vaccine-autism theory, Dr. Walker suggested that the objectives and findings of this study be considered in the “proper context,” noting that “our goal is to discover the biology of bowel disease in these children and to gain insight into the most effective ways to treat it.”
Relieving the bowel discomfort is a top priority. “These kids experience severe stomachaches every hour of every day, and many of them are nonverbal, so they can't communicate their pain,” he said. Instead, they exhibit certain behaviors that are often considered characteristic of their autism, such as leaning over the edge of a table or chair for hours at a time.
Identification and treatment of the bowel disease can lead to improvements in other areas, Dr. Walker noted. “There is case after case where kids improve cognitively, behaviorally, and biomedically when the bowel disease is treated. Right now, that is our goal.”