One thing to understand when talking about tics and Tourette Syndrome is that tics are not Tourette Syndrome.
Instead, Tourette Syndrome is a type of tic disorder.
What Causes Tics and Tourette Syndrome?
You should also understand that tics are common.
In fact, about 20% of school age kids get tics, although few have them for more than a year. These motor or vocal tics (involuntary eye blinking, head jerking, shoulder shrugging, humming, sniffing, grunting, throat clearing, or yelling out a word or phrase) are most common when kids are between the ages of 10 to 12 years old, but may start as early as age 6 to 7 years.
Not only are these tics common, but they are thought to be normal and very often go away without treatment. About 97% of kids have complete resolution of their tics within a year or so.
The rest might go on to have a persistent motor or vocal tic disorder though.
And some kids with persistent motor and vocal tics might have Tourette Syndrome.
Why?
“While environmental factors and illness may influence ticcing, the weight of evidence argues that tic disorders and their comorbidities are inherited/genetic. The inheritance pattern can be subtle and unexpected. In clinic, we often see a parent, while either indicating that they experienced childhood tics that remitted or that no one in the immediate family ever had tics, demonstrating frequent subtle tics.”
Kids and Tics: What’s “Normal” and When to see a Specialist
That’s right. Genetics.
Tics and Tourette Syndrome often run in families.
Do Vaccines Cause Tics or Tourette Syndrome?
As you might suspect, vaccines do not cause tics or Tourette Syndrome.
Neither does thimerosal, which used to be a common preservative in vaccines.
That’s not surprising, as neither tics nor Tourette Syndrome are new conditions.
Why can you find studies that try to link thimerosal and vaccines to tics and Tourette Syndrome? Because they are poorly done studies by folks who routinely do studies that try to make it look like vaccines cause everything from autism and tics to ADHD.
Other studies have found no link between thimerosal and tics, including the study Neuropsychological Performance 10 Years After Immunization in Infancy With Thimerosal-Containing Vaccines.
Even the studies that found some association weren’t very convincing.
“With the possible exception of tics, there was no evidence that thimerosal exposure via DTP/DT vaccines causes neurodevelopmental disorders.”
Andrews et al on Thimerosal exposure in infants and developmental disorders: a retrospective cohort study in the United kingdom does not support a causal association.
One study, for example, did actually find some association between thimerosal and tics.
Maybe.
Infants who received one dose of DTP with thimerosal had a higher rate of tics than infants who didn’t. The strange thing about the study though is that infants who had two or three doses also had a higher rate than getting just one dose and a similar rate as kids who didn’t get any vaccines with thimerosal.
“We did find one statistically significant association between exposure to thimerosal-containing vaccines and the presence of tics among boys, however, this association was not replicated in girls. Previous associations between thimerosal containing vaccines and tics were found by Verstraeten et al. (2003) and Andrews et al. (2004) but the findings were not sex specific. Our tic finding was also consistent with the tic finding reported in the original study (Thompson et al., 2007).”
John Barile et al on Thimerosal Exposure in Early Life and Neuropsychological Outcomes 7–10 Years Later
None of this sounds like evidence that vaccines cause tics, does it?
No.
None of these studies found clinically significant evidence that vaccines cause tics or Tourette Syndrome.
What about other thimerosal-free vaccines? There have been no reports of increased rates of tics or Tourette Syndrome with any thimerosal-free vaccines either.
“There were 17 reports of Tourette’s disorder. Two patients developed movement disorders following 4vHPV with symptoms similar to Tourette’s, but did not have a definitive clinical diagnosis of Tourette’s disorder from a specialist (i.e., a neurologist or psychiatrist). In three additional reports, patients had a Tourette’s diagnosis or displayed symptoms of Tourette’s prior to vaccination. The remaining 12 reports were submitted by one physician who read on internet websites about possible Tourette disorder occurring after vaccines, but he had no firsthand information on any patient. None of these 12 reports could be verified.”
Arana et al on Post-licensure safety monitoring of quadrivalent human papillomavirus vaccine in the Vaccine Adverse Event Reporting System (VAERS), 2009-2015.
There is no evidence that vaccines cause tics or Tourette Syndrome.
In fact, at the December 2017 meeting of the Advisory Committee on Childhood Vaccines, there was a petition to add tics as a vaccine table injury. After reviewing all available evidence, including the work of William Thompson, the so-called CDC Whistleblower, the committee voted 5-1 for the option to not add tics as an injury to the Table. They also didn’t add asthma or PANDAS to the vaccine injury table, despite some folks petitioning them to do so.
That’s likely not a surprise to folks who know that vaccines are safe.
What to Know About Tics and Tourette Syndrome
- Kids and Tics: What’s “Normal” and When to see a Specialist
- Tourette Syndrome and Other Tic Disorders
- Gilles de la Tourette and the discovery of Tourette syndrome. Includes a translation of his 1884 article.
- Advisory Committee on Childhood Vaccines Meetings
- CDC – Diagnosing Tic Disorders
- Stand Up for Tourette Syndrome
- What is Tourette
- Tics and Tourette Syndrome
- AAP – Tics, Tourette Syndrome, and OCD
- Adverse Effects of Vaccines: Evidence and Causality
- Chiropractic “Research” on Tourette Syndrome: The Trouble with Case Reports…..
- More bad epidemiology from Dr. Brian S. Hooker and friends
- Mark Geier, David Geier and the VSD
- Joint Statement of AAFP, AAP, ACIP, and the USPHS on Thimerosal in Childhood Vaccines
- CDC Study: “Infant and Environmental Exposures to Thimerosal and Neuropsychological Outcomes at Ages 7 to 10 Years”
- Study – Thimerosal exposure in infants and developmental disorders: a retrospective cohort study in the United kingdom does not support a causal association.
- Study – Safety of thimerosal-containing vaccines: a two-phased study of computerized health maintenance organization databases.
- Study – Neuropsychological Performance 10 Years After Immunization in Infancy With Thimerosal-Containing Vaccines
- Study – Thimerosal Exposure in Early Life and Neuropsychological Outcomes 7–10 Years Later
- Study – Early Thimerosal Exposure and Neuropsychological Outcomes at 7 to 10 Years
- Study – White Paper on studying the safety of the childhood immunization schedule in the Vaccine Safety Datalink.
- Study – Post-licensure safety monitoring of quadrivalent human papillomavirus vaccine in the Vaccine Adverse Event Reporting System (VAERS), 2009–2015
- Study – Anxiety-related adverse events following immunization (AEFI): A systematic review of published clusters of illness.
- Vaccine Whistleblower: An antivaccine “exposé” full of sound and fury, signifying nothing
- Why Does Robert F. Kennedy Jr. Get Brain Science So Wrong?
Last Updated on September 30, 2018