Autism affects an estimated 1 in 150 births each year, according to 2007 statistics from the Centers for Disease Control. Roughly translated, this means about 1.5 million Americans today are believed to have some form of the disorder, and the number is on the rise.

Based on statistics from the U.S. Department of Education and other governmental agencies, autism is growing at a startling rate of 10 to 17 percent each year. At this rate, the prevalence of autism could reach 4 million Americans in the next decade.

April is Autism Awareness Month, and here are some important questions and answers you should know about the disorder.

• What is autism? Autism is a complex developmental disability that typically appears during the first three years of life and is the result of a neurological disorder that affects the normal functioning of the brain. Children with autism typically show difficulties in verbal and non-verbal communication, social interactions, and leisure or play activities.
       
  Autism is one of five disorders that falls under the umbrella of Pervasive Developmental Disorders, a category of neurological disorders characterized by "severe and pervasive impairment in several areas of development." Other PDDs include Asperger syndrome, Rett syndrome and childhood disintegrative disorder. Boys are four times more likely to have autism than girls.
       
• What are some common signs of autism? Parents are usually the first to notice symptoms of autism in their child. As early as infancy, a baby with autism may not respond to others or may focus intently on one item for long periods of time. A child with autism may appear to develop normally, but then withdraw and become indifferent to social engagement.
      
  Children with autism may not respond to their names being called and often avoid eye contact with others. They have difficulty interpreting what others are thinking or feeling because they can’t understand social cues, such as tone of voice or facial expressions, and may not be watching others’ faces for clues about appropriate behavior.
      
  Autistic children often engage in repetitive movements, such as swaying, or in self-abusive behavior, such as head-banging. They may not begin speaking at the same time as other children their age, and might be heard referring to themselves by their name, or in the third person, instead of "I" or "me." Some autistic children speak in a sing-song voice on a small range of topics with little regard for the interests of the person to whom they are speaking.
       
  Some children with autism have a reduced sensitivity to pain, but may be overly sensitive to sound and touch. These kinds of reactions may explain their resistance to being cuddled or hugged.
           
• How is autism diagnosed? The symptoms and severity of autism vary and may go unrecognized, especially in mildly affected children or when it is hidden by a more serious developmental issue. Physicians often use a questionnaire or other screening tools to gather information about a child’s development and behavior. Some screening tools rely solely on parental observations; others rely on a combination of parent and physician observations. If screening tools indicate the possibility of autism, a more comprehensive evaluation will be recommended.
         
  Because autism is complex, a comprehensive evaluation by a multidisciplinary team including a psychologist, neurologist, psychiatrist, speech therapist and other professionals is the best way to test for the disorder. This team makes a thorough neurological assessment and uses in-depth cognitive and language testing. Because hearing problems can cause behaviors that could be mistaken for autism, children with delayed speech development should also have their hearing checked. After a thorough evaluation, the team usually meets with parents to explain the results and present a diagnosis.
       
• What causes autism? Scientists are uncertain what causes autism, but it is likely that a child’s environment and genetics play a role. Researchers have identified several genes associated with the disorder. Some studies of people with autism have found irregularities in regions of the brain, while other have indicated that people with autism have abnormal levels of serotonin or other neurotransmitters in the brain. Both findings suggest that autism could result from the disruption of normal brain development early in fetal development caused by defects in genes that control brain growth and that regulate how neurons communicate with each other. The findings require further study, however.
        
  Many parents, and a few physicians, have suggested that one of two different substances might cause autism: the Measles - Mumps - Rubella vaccine, MMR, and the mercury in thimerosal, which was used as a preservative in certain vaccines until 2001. However, the Centers for Disease Control examined all existing studies that suggest a causal relationship between the MMR vaccine and autism, and concluded that these studies have significant weaknesses. Additionally, no concrete evidence has shown that thimerosal is linked to autism, but the Centers for Disease Control and Prevention and the American Academy of Pediatrics pushed for its elimination to reduce unnecessary mercury exposure and quell the fears of parents who might otherwise not get their children vaccinated.
       
• What role do genetics play? A few recent studies indicate that there could be a genetic predisposition to autism. Families who have one autistic child, have a one in 20 chance of having a second child with the disorder, which is greater than the risk for the general population. In some cases parents or relatives of an autistic child show mild impairments in social and communicative skills or engage in repetitive behaviors. Evidence also suggests that some emotional disorders, such as manic depression, occur more frequently than average in the families of children who are autistic.
       
• How is autism treated? The conventional medical view is that there is no cure for autism. This approach relies on behavioral interventions and therapies which are designed to aid specific symptoms and may produce visible improvement. An ideal treatment plan combines therapies and interventions that target the core symptoms, including impaired social interaction, communication problems and obsessive or repetitive routines. Most professionals agree that the earlier the intervention, the better. Research shows that when intervention is provided to children from birth to age 3, it has a dramatic impact on reducing the symptoms of autism spectrum disorders.
         
  An alternative viewpoint, held by many parents of autistic children, is that autism is a treatable disease resulting from some environmental insult to a genetically susceptible child. Many professionals who share this view have observed autistic children improving with dietary interventions such as a gluten-free casein-free diet. However, there are many children who do not show improvement with dietary interventions. This suggests that autism may be the final behavioral result of two or more diseases that affect childhood brain function. In the face of so much yet to learn, it is important for doctors and parents both to keep an open mind about new approaches.

Though the disorder is prevalent, the future is bright for autistic children. Studies in early childhood development suggest that the youngest brains are the most flexible. In autism, early intervention may provide a tremendous amount of progress in children before they enter kindergarten, often reducing the need for more intensive support. The majority of children with autism improve as they get therapy and mature. But understanding all the issues related to the disorder is an important first step.

MCG Health, Inc. (d/b/a MCGHealth) is a not-for-profit corporation operating the MCGHealth Medical Center, MCGHealth Children’s Medical Center, the Georgia Radiation Therapy Center, and related outpatient facilities and services throughout the state. For more information, please visit mcghealth.org.