Vaccines don’t cause autism. What does?

The myth that autism is caused by childhood vaccines has been thoroughly debunked. Hundreds of studies have found vaccines to be safe, and the World Health Organization estimates that over the past 50 years, immunizations have saved 154 million lives around the world.

A complex condition

Finding the causes of autism is complicated because it’s not a single disorder. Autism is a spectrum, not a single narrow disease. It’s many, many things under one umbrella. Scientists have found a variety of risk factors for autism, most of which exist before birth, but there is no single cause for a neurological and developmental condition that affects how people interact with others, communicate, learn, and behave.

A number of the traits sometimes seen in people with autism — such as being sensitive to loud noises, for example, or finding it difficult to interpret social cues — are also found in people who have not been diagnosed with autism. Doctors diagnose autism based on a person’s behavior, noting that there is no simple test for the condition, as there is for Covid or diabetes.

Genetic vulnerability

Doctors have long known that genes play a large role in autism, simply by noting that autism can run in families. For example, in identical twins — who share all of their DNA — if one twin has autism, the other usually does, as well. In the case of fraternal twins — who share about half their DNA — if one fraternal twin has autism, the chance that the other will have autism ranges from 53% to 67%.

Scientists have identified more than 100 genes related to autism, and genes are believed to play a role in 60% to 80% of cases. Yet genes clearly don’t explain every case of autism. Autism is very different from conditions like sickle cell anemia or cystic fibrosis, which are caused by a single gene.

Prenatal vulnerability

Many of the known risk factors for autistic characteristics occur before birth or at the time of delivery. Babies who experience complications at birth, such as their umbilical cord becoming wrapped around their neck, have a higher risk of autism. So do babies born prematurely, perhaps because of something that happened in the womb.

Children are also slightly more likely to be diagnosed with autism if they have older fathers and possibly if they have older mothers. It’s not clear if something in the biology of older parents causes a child to have a higher risk of autism, or if socioeconomic issues could play a role. A mother’s health influences her child’s autism risk in several ways: Children have a greater chance of being diagnosed with autism if their mothers were exposed to high levels of air pollution or developed a serious infection, such as the flu or pneumonia, while pregnant.

Conclusion

Autism is a complex condition with no single cause. Vaccines do not cause autism, and hundreds of studies have found them to be safe. The causes of autism are multifaceted and may include genetic, prenatal, and environmental factors. While researchers continue to study the factors that influence the development of autistic traits, the one thing we know doesn’t cause autism is vaccines.

FAQs

Q: What are the known risk factors for autism?

A: Many of the known risk factors for autistic characteristics occur before birth or at the time of delivery, including complications at birth, premature birth, older fathers, and older mothers. Genetic vulnerability and environmental exposures may also play a role.

Q: Is there a single cause for autism?

A: No, there is no single cause for autism. It’s a complex condition that may be influenced by multiple genetic and environmental factors.

Q: Can vaccines cause autism?

A: No, vaccines do not cause autism. Hundreds of studies have found vaccines to be safe, and the World Health Organization estimates that over the past 50 years, immunizations have saved 154 million lives around the world.

Q: What is being done to support people with autism?

A: While some research is being conducted to better understand the causes of autism, more attention and resources are needed to support people with autism and their families. Only 8.4% of the $419 million spent on autism research in the United States is devoted to support and services for people with autism.