Autism is a brain disorder affecting approximately 5 per thousand children in which there is a difficulty in social relations, difficulty in communication, and a lack of imaginative and creative play. There seems to be an undetermined genetic tendency towards autism and it occurs more commonly in boys (approximately 75% are males). Although there have been numerous claims of association with vaccine administration, this has been studied extensively and there does not seem to be any correlation. There has been an increase in the diagnosis of Autism recently; this is because of better diagnosis, rather than an inherent increase in the development of Autism.

Autism generally does not appear until the second or third years of life - but is best treated if discovered early and therapy is begun as soon as possible.

According to The National Center on Birth Defects and Developmental Disabilities, a child or adult with autism might have the following signs and symptoms:

not play "pretend" games (pretend to "feed" a doll)
not point at objects to show interest (point at an airplane flying over)
not look at objects when another person points at them
have trouble relating to others or not have an interest in other people at all
avoid eye contact and want to be alone
have trouble understanding other people's feelings or talking about their own feelings
prefer not to be held or cuddled or might cuddle only when they want to
appear to be unaware when other people talk to them but respond to other sounds
be very interested in people, but not know how to talk, play, or relate to them
repeat or echo words or phrases said to them, or repeat words or phrases in place of 
normal language (echolalia)
have trouble expressing their needs using typical words or motions
repeat actions over and over again
have trouble adapting when a routine changes
have unusual reactions to the way things smell, taste, look, feel, or sound
lose skills they once had (for instance, stop saying words they were once using)

If you or your doctor think there could be a problem, ask for a referral to see a developmental pediatrician or other specialist, and you can contact your local early intervention agency (for children under 3) or public school (for children 3 and older).