Autism Spectrum Disorders Health Center

Report: Fever Improves Autism Symptoms

Dec. 3, 2007 -- Children with autism appear to improve when they have a fever, according to intriguing new research that could lead to a better understanding of the disorder.

Fever was associated with less hyperactivity, improved communication, and less irritability in the study involving children with autism and related disorders.

Anecdotal reports of improvements in autism symptoms related to fever have circulated for years, but the research represents the first scientific investigation into the observed association.

While kids with autism might be expected to be calmer and less hyperactive when they have fevers, the improvement in communication and socialization seen in the study suggests that fever directly affects brain function, pediatric neurologist Andrew Zimmerman, MD, of Baltimore's Kennedy Krieger Institute, tells WebMD.

"The improvement in symptoms may mean the underlying wiring of the brain (of an autistic child) develops more normally than we have thought," he says, adding that the problem may lie with the connections within the brain responsible for sending information.

"Somehow fever appears to be changing the ability to make these connections," he says.

4 out of 5 Kids With Fever Improved

The study involved 30 children with autism spectrum disorders, including autism, who were observed by parents during and immediately after experiencing a fever of 100.4 degrees or greater, and seven days after being without fever.

The parents were asked to complete standardized behavior questionnaires during the three time points designed to assess behavior. Parents of children with autism spectrum disorders who did not experience fever were also surveyed at related time points.

More than 80% of the children with fever in the study showed some improvement in behavior during temperature elevations, the researchers reported in the December issue of the journal Pediatrics.

Further analysis showed that behavior improvement was not dependent on the degree of fever.

Zimmerman and lead researcher Laura K. Curran, PhD, tell WebMD that more study is needed to confirm the findings.

"We'd like to interview more families to better understand this," Zimmerman says. "And at the chemical level, we'd like to have blood samples from children while they have fever to analyze what is going on."