I was amazed to recently discover that Autism is a disorder and not an Illness. So while an Illness may not have a good chance of recovery, Disorders have a greater chance.

Autism is a developmental disorder characterized by troubles with social interaction and communication. Often there is also restricted and repetitive behavior.Parents usually notice signs in the first two or three years of their child's life.These signs often develop gradually, though some children with autism reach their developmental milestones at a normal pace and then worsen.

Autism is caused by a combination of genetic and environmental factors. Risk factors include certain infections during pregnancy such as rubella as well as valproic acid, alcohol, or cocaine use during pregnancy.Controversies surround other proposed environmental causes; for example the vaccine hypotheses, which have been disproven. Autism affects information processing in the brain by altering how nerve cells and their synapses connect and organize; how this occurs is not well understood.In the DSM V, autism is included within the autism spectrum (ASDs), along with Asperger syndrome which is less severe, and pervasive developmental disorder, not otherwise specified (PDD-NOS).

Read full article here
https://en.wikipedia.org/wiki/Autism