If you’re an autism parent, you may have noticed an unexpected clarity to your child’s behavior when they are sick. Whether they seem to make eye contact more easily or their speech is a bit clearer, many autism parents will swear that some of their child’s autism traits lessen with a fever—and new research backs them up.
Parents and researchers alike have noted this connection for some time.
Back in 2017, a study led by Catherine Lord, director of the Center for Autism and the Developing Brain at New York-Presbyterian Hospital in White Plains, New York, found that parents reported improvements in their child’s behavior or communication when they had a fever.
The study revealed that 17 percent of children with autism are calmer and more communicative than usual when they have a fever, with parents reporting “improvements across a range of domains during fever including cognition, communication, repetitive behaviors, social interaction, and behavior.” Lord’s study also found that children more severely affected by autism are more likely to see improvements during a fever.
A recent scientific study went even deeper.
As interest in this parent-reported phenomenon continued, researchers’ interest in studying it grew. Recently, researchers led by Gloria Choi at Massachusetts Institute of Technology studied the effects of fever on mice exposed to a molecule called interleukin 17A, or IL-17A.
The molecule IL-17A has been studied greatly over the last few years. It is produced by the immune system during a fever, but is also found to be elevated in many autistic children. Scientists are now exposing test groups of mice to it in the womb as a way to further autism research. Choi and her team studied the effect of fever on mice who’ve been exposed to IL-17A, which causes them to exhibit autism-like traits.
When fever was mimicked in these mice, their autistic traits lessened—but only if an immune response was triggered, not if their body temperature was simply raised. Researchers found that fever in mice with autism traits “quiets their neural activity and enhances their sociability.” These are two areas that have marked deficits in individuals with autism.
The new work strengthens the link between IL-17A and autism. If mice exposed to IL-17A are reactive to fevers in the same way children with autism are, this molecule may have even more significance in individuals with autism. Furthermore, it strengthens the evidence that fever has an impact on autism symptoms.
The yet unpublished findings of Choi’s studies were presented at the 2019 Society for Neuroscience annual meeting in Chicago, Illinois. Experts feel that the findings could help them target therapies that can reap the benefits of a fever without the side effects.