Vaccines and autism: Separating the facts from the fiction

No scientific evidence points to childhood vaccinations causing autism, yet fears persist

Boy and girl are playing doctor with toys at the doctors office. Preparation for vaccine.

Despite comprehensive research saying otherwise, the rumor mill and unfounded reports perpetuate fear that child vaccinations are at the root of autism.

Numerous research studies have proven that autism spectrum disorder is not related to vaccination. This research has been conducted by the nation’s leading health experts, including the Centers for Disease Control and Prevention, National Institutes of Health, Autism Science Foundation, American Academy of Pediatrics and others. They all concur that there is no evidence vaccinations cause autism. So why do the rumors persist?

If you are the parent of a child with autism spectrum disorder, it’s understandable — and commendable — that you are searching for answers. It’s also understandable you want to know what causes this disorder.

Fact: There is no single cause of autism.

One of the reasons that the cause of this disease has been so hard to diagnose is because symptoms and behaviors vary so greatly among patients.

Medical experts know ASD is a neurodevelopmental disorder that affects early brain development. Communication problems, poor social interaction and repetitive specific patterns of behavior are common symptoms.

But because symptoms vary so greatly, autism is considered a “spectrum” disorder, meaning ASD is a group of disorders with similar features. People with ASD can be extremely intelligent, even gifted. Or they can have very low intelligence. Regardless, they interact, behave and learn differently from what we think of as typical.

Fact: Science has found no vaccine-autism link.

No scientific evidence has found a causal link between ASD and childhood vaccinations. More than 10 years ago, researchers agreed ASD and a possible relation to vaccines needed to be studied. The number of vaccines children were receiving was increasing. At the same time, the number of children with autism was on the rise.

“Fortunately, this was a question that could be studied — and answered — by science,” Autism Science Foundation leaders assert. “We looked at children who received vaccines and those who didn’t, or who received them on a different, slower schedule. There was no difference in their neurological outcomes. The results of studies are very clear; the data show no relationship between vaccines and autism.”

Fact: Multiple studies on vaccines and autism agree.

The Autism Science Foundation doesn’t ask you to take its word for it. ASF offers the studies as a recommended reading list for parents. Nor is it the only professional organization engaging in research on this topic.

The AAP released a statement including this information: “The American Academy of Pediatrics reiterates that vaccines protect children’s health and save lives. They prevent life-threatening diseases, including forms of cancer. Vaccines have been part of the fabric of our society for decades and are the most significant medical innovation of our time.

“Vaccines are safe. Vaccines are effective. Vaccines save lives. Claims that vaccines are linked to autism, or are unsafe when administered according to the recommended schedule, have been disproven by a robust body of medical literature.”

“There has been enormous debate regarding the possibility of a link between childhood vaccinations and the subsequent development of autism,” according to NIH. “This has in recent times become a major public health issue with vaccine-preventable diseases increasing in the community due to the fear of a ‘link’ between vaccinations and autism.

“We performed a meta-analysis to summarize available evidence from case-control and cohort studies on this topic. Reviewers extracted data on study characteristics, methods and outcomes. Disagreement was resolved by consensus with another author. Five cohort studies involving 1,256,407 children, and five case-control studies involving 9,920 children were included in this analysis. The cohort data revealed no relationship between vaccination and autism.”

NIH invites you to check out studies detailing its evidence.

“Cases of autism have risen over the last 20 years, from about 1 in 200 children in the 1990s to 1 in 88 today,” the CDC says. “This increase has led doctors and researchers to try to find out what is causing autism. But, much undue blame has fallen on vaccinations, especially from parents. Multiple CDC studies have debunked the link between vaccines and autism.”

A 2013 CDC study looked at the number of antigens (substances in vaccines causing the body’s immune system to produce disease-fighting antibodies) from vaccines during the first two years of life (the time period when it is thought autism is developing). The results showed that the total amount of antigen from vaccines received was the same between children with ASD and those that did not have ASD. The CDC concluded, “Vaccine ingredients do not cause autism.”

Fact: The original study claiming a vaccine-autism link has been debunked many times.

The autism-vaccination scare was fueled by a 1998 study a British scientist published, claiming there was a definite link. But this study was proven to be “erroneous, unscientific, and fraudulent.” The doctor who wrote it even lost his license. Yet, this study continues to be used as evidence today, continuing the spread of erroneous information.

Some say, “It’s not every childhood vaccination causing the problem. I’ve seen articles or media stories that link autism to thimerosal, a vaccination ingredient, and certain types of vaccinations – namely the MMR (measles, mumps and rubella). Or maybe children are just being given too many vaccines at the same time. I’ve heard that too.”

So is thimerosal the culprit? No. Due to autism-vaccination concerns at the time, thimerosal (a preservative included in childhood vaccinations) was removed from almost all vaccinations in 2001. Since its removal, autism cases have continued to rise.

Mercury also gets the blame. Some people speculate that mercury consumption from vaccines may be at the root of ASD. Reputable CDC studies using several different methods found mercury was not a cause of autism. Nor did the number of children diagnosed with autism decrease when mercury was removed from vaccines.

“Today, except for some flu vaccines in multi-dose vials, no recommended childhood vaccines contain thimerosal as a preservative,” the CDC states. “In all other recommended childhood vaccines, no thimerosal is present, or the amount of thimerosal is close to zero. No reputable scientific studies have ever found an association between thimerosal in vaccines and autism.”

In addition, the mercury found in multi-dose vials is different and less dangerous than the type of mercury found in fish, animals and the environment. Methylmercury, the type of mercury found in certain kinds of fish, can be dangerous and toxic at high levels. Ethylmercury, or the mercury in thimerosal, is less likely to cause harm, as it’s eliminated from the human body more quickly than methylmercury.

Since 2003, nine CDC-funded or conducted studies have been done looking for links between vaccination ingredients and ASD. None of the studies found any connection. If you read the NIH case studies, you will see that NIH case-control data also found no evidence for increased risk of developing autism or ASD following MMR vaccinations.

Fact: Autism spectrum disorder is likely genetic.

One of the things continuing to stir the pot is the cause of ASD is not known. Current research findings suggest there is a strong hereditary component. Scientists think ASD results from a complex interaction between several genes that play roles in brain signaling and development.

Environmental, biologic and genetic factors are believed to contribute to ASD. Almost all scientists agree genetics is a strong factor. Research has shown children who have a sibling with ASD are at higher risk. ASD also occurs more often in people who have certain genetic or chromosomal conditions. Children born to older parents are at greater risk for ASD.

Critical evidence exists suggesting the period for developing ASD occurs before, during and immediately after birth. Diagnosis of ASD usually takes time. There is no medical test defining it. Doctors look at the child’s behavior and development to make a diagnosis.

Sometimes, it can be detected at 18 months or younger. You can expect a fairly reliable diagnosis by the time your child is age 2. Medical specialists now consider a diagnosis of ASD to include several conditions that used to be diagnosed as separate. These include autistic disorder, pervasive developmental disorder not otherwise specified (PDD-NOS) and Asperger syndrome.

Fact: Some parents still aren’t sure.

Some parental beliefs refuse to disappear. A Journal of Preventative Medicine study published in May 2017 reported that nearly 8 out of 10 physicians report at least one vaccine refusal from a parent. Eight percent of physicians report refusals for more than 10 percent of children in their practice. According to a Harris Interactive/HealthDay poll published in January 2011, 18 percent of Americans say vaccines cause autism and 30 percent are not sure.

Families with one child with ASD are less likely to vaccinate younger siblings. Why? Because they are afraid the child with ASD got it from having the MMR vaccination. Even in studies where children were put on an alternate MMR schedule, autism diagnoses did not change.

And if you’re looking for a cure, you are probably running into a lot of fiction, too. The following treatments being sold have no established evidence of effectiveness: camel milk, gluten- and casein-free diets, certain vitamin supplements, secretin injections, anti-fungal agents, chelation, giant electromagnets, hyperbaric oxygen therapy, holding therapy, nicotine patch or actual snake oil.

Fact: Vaccination prevents many diseases.

More and more children are getting sick from vaccine-preventable diseases. Get your children vaccinated and encourage your friends to do so, too. Share with them what you have learned about the scientific data related to the non-effects of vaccines on autism.

Stay informed. CDC and numerous other health leaders are searching for ASD causes and factors. Resources are continually being developed to help identify and treat children with ASD as early as possible.

Currently, CDC is working on one of the largest United States studies ever done. Called Study to Explore Early Development (SEED), it is designed to find out if or how pregnancy or genetic, environmental and behavioral factors may put children at risk for ASD and other developmental disabilities.

Finally, trust your pediatrician. The AAP says, “Delaying vaccines only leaves a child at risk of disease. Vaccines keep communities healthy and protect some of the most vulnerable in our society, including the elderly, and children who are too young to be vaccinated or have compromised immune systems. Pediatricians partner with parents to provide the best care for their children, and what is best for children is to be fully vaccinated.”

If you have concerns about your child’s development, use the resources available to you. If your child isn’t receiving state assistance, call for a free evaluation. Research also shows when a child with ASD receives intervention services at an early age, development improves.

Contact your state’s public early childhood system for more information. You do not need a doctor’s referral — or even a medical diagnosis of autism for your child — to access these services. If you do not know where to call in your state, you can get the contact information by calling the Early Childhood Technical Assistance Center (ECTA) at (919) 962-2001.

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Posted In Behavioral Health, Children's, Health Information, Immunizations, Inclusion at Sanford, Pregnancy, Women's