As a scientist, I regularly scan the popular news for articles on disease, medicine, and biology. The internet affords the general public an opportunity to search the vastness of the web for information on disease symptoms, as well as new medical cures and research breakthroughs. But the problem with such vast amounts of easily accessible information is that the vetting process for accuracy breaks down. An added complication is the general inability of scientists and doctors to properly explain science and medicine to non-specialists. Journalists step in to act as conduits between the two groups, and often the integrity and interpretation of the message are compromised.
Areas of biomedicine in which the disconnect between science and the public is most obvious – at least in my opinion – are DNA-based technologies, genetically modified foods, and vaccines. The antagonism against the latter has escalated in the past few years, thanks to the involvement of celebrities such as Jenny McCarthy. These individuals oppose vaccination for diseases such as measles, mumps, rubella (MMR), pertussis (whooping cough), and human papilloma virus (HPV) that causes cancer.
I typically treat journalism that fails to properly explain scientific findings with a mixture of exasperation and resignation. However, several recent events morphed mild irritation into full-blown disgust at the deliberate misinformation and willful distortion of scientific data that is being messaged by anti-vaccine advocates, including celebrities and the every day citizen.
First, a twitter friend (@bccohan) tweeted a link to a news story reporting that a vaccine for Lyme Disease is being widely used, but only on dogs. That’s right, despite the vaccine having been available since 1998, and even though Lyme Disease is the most prevalent tick-borne disease in the US, the vaccine can’t be administered to humans. You can thank “vaccine victims” who claimed based on anecdotal evidence that the Lyme vaccine causes arthritis, and overly litigious lawyers who eagerly assembled class-action suits on their behalves.
Second was the announcement that Elisabeth Hasselback’s co-host seat on The View couch would be filled by Jenny McCarthy. Thus, one of the world’s most famous and scientifically illiterate anti-vaccine advocates has been given an even larger national platform.
For those who don’t know, McCarthy’s son suffers/suffered from autism that she asserts appeared after he received vaccinations as an infant. Because of increased awareness of autism and McCarthy’s visibility in pop culture, it was quite easy for people to relate to McCarthy’s story and adopt her uninformed and unsubstantiated conclusion. She has since claimed that her son is completely cured of his autism, due to her implementation of untested, alternative medicine. She even wrote a book about it. Yet, it remains unproven that: a) her son even had autism, and b) that vaccines actually cause autism.
However, based on her own misguided beliefs and fueled by a scientific study published 15 years ago, McCarthy and other opponents of childhood immunization have formed the“Vaccine Truthers”. The Anti-Vaccine Crowd champions a cause that it does not completely understand, and that, in fact, has been scientifically debunked. Nevertheless, according to a 2011 University of Michigan study “nearly a quarter of all parents still place ‘some faith’ in celebrities’ counter-claims on vaccinations”.
Autism, more properly known as Autism Spectrum Disorder (ASD), represents a collection of developmental phenotypes (symptoms). Boys are four times more likely to have autism than girls. In 2012, the CDC reported a rate of 1 in 88 (1%) American children, but in 2013, revised that number to 1:50 (2%) children. It is a fair – and accurate, I think – argument that autism is not necessarily increasing in the population, but that awareness is heightened and, more importantly, doctors have become much better at diagnosing the symptoms.
Scientific studies published starting in 1961 to present day nearly all agree that autism fundamentally and primarily has a genetic basis.
Translation: most autism is caused by genetics.
How do we know this?
- the same disease symptoms or traits have been observed in more than one unrelated family.
- the same disease symptoms or traits have been observed in more than one member of a family (i.e., parent and child or among siblings).
- the same disease incidence is observed in sets of identical twins (genetically identical) but not in sets of fraternal twins (genetically share 50% of their DNA).
Many genes have been implicated in causing autism and much research is being done to identify the genes and the mutations that cause autism. The spectrum of phenotypes is due to the fact that different genes are altered in different autism individuals (what we geneticists call genetic heterogeneity), and the behavior or function of the same genes can even differ among individuals (called genetic penetrance or variable expressivity).
Genes “talk” to or depend on each other to function properly for normal brain development. Based on the combination of genes that are mutated and the types of DNA changes, symptoms can vary between autism individuals. Finally, genes interact not only with other genes, but also with environmental factors, such as amounts and types of nutrients or exposures to pollutants (diesel exhaust, mercury, etc.). Thus, autism symptoms may differ depending on whether an individual – or more precisely, that individual’s mother – was exposed to certain environmental triggers that piggybacked with a cadre of mutant genes to alter brain development and function in autism patients.
So, what about vaccines? They are technically environmental exposures, right? Yes. But there is no scientific evidence to support that vaccines cause autism.
So how did the link between the two come about in the first place?
The anti-vaccine movement originated with the English biologist Alfred Wallace, a contemporary of Charles Darwin who believed compulsory vaccination was unethical. The link of vaccination with disease and disability is thought to have emerged here across the pond in 1982 based on an Emmy award-winning documentary produced by investigative journalist Lea Thompson.
A few years later, the link of vaccines to autism appeared when British researcher Dr. Andrew Wakefield published an article in the medical journal The Lancet, claiming that eight children developed symptoms of autism one month after being vaccinated for measles (MMR). He and his co-authors asserted that the vaccines caused inflammation, especially in the gut, that drove molecules derived from food and normally not found in the bloodstream into the blood. They were then carried to the brain, where they triggered detrimental developmental effects.
The results of this study – and essentially only this study – have fueled the anti-vaccine movement for the past 15 years. But this 1998 study was never replicated, and by that I mean that other scientists actually tried but were unable to find a link between MMR vaccine and autism.
In 2004, ten of the co-authors on the Wakefield The Lancet paper retracted their claims of a MMR vaccine-autism link. Then, The Lancet itself fully retracted the paper in 2010. In that same year, a U.S. Federal Vaccine Claims Court ruled that MMR vaccine, thimerosol (an adjuvant added to vaccines to help trigger an immune response), or both, do not cause autism.
Nevertheless, the damage was done, and many parents around the world immediately reacted by choosing not to vaccinate their children. And the result was that measles cases have increased, hitting a 15-year high in the U.S. in 2011.
In these recent U.S. measles cases, the infections originated in another country. But they were transmitted by someone who came in contact with the American children, all of whom were verified to be unimmunized.
Infectious diseases by definition are transmitted or communicated by people-to-people or people-to-secretion contact. In these modern times of population growth, displacement and migration of people, and common travel between distant destinations, vaccination is not just a U.S. issue. It is a global issue.
Vaccines, like any medicine or pharmaceutical agent, are associated with some side effects. They are usually rare and primarily correspond to reactions to injection of the vaccine, such as fever, rash, headache, or redness and swelling at the site of the needle stick. These symptoms are largely inflammatory responses to what the body considers a new substance – think: stranger-danger! These responses are a normal part of our immune reaction that mobilizes to investigate foreign or uncatalogued substances and then stores information about them in the body’s immune response file cabinet.
None of these side effects or responses equate to diseases such as autism. In fact, the Institute of Medicine – part of the Department of Health and Human Services – published an official report in 2011, concluding “few health problems are caused by or clearly associated with vaccines”
Vaccines protect children and adults from infectious diseases. Since the MMR vaccine was first introduced in 1963, our country has had a 99% reduction in the incidence of measles. Similarly, the polio vaccine was developed and administered in the mid-1950s. By 1979, polio was eradicated in the United States.
One may choose to be anti-vaccine for many reasons. But to be anti-vaccine by claiming that scientific evidence supports that vaccines cause disease, death, or harm is simply not factual.
The bottom line: science has proven that vaccines save lives. Moreover, by not vaccinating a child, parents put that child – and other children and adults – at risk.