Childhood diseases like mumps and measles, once dangerous and sometimes fatal ailments, had largely been brought under control by the end of the 20th century due to almost universal immunization. But in the past ten years, a small contingent of parents and researchers has been able to sow enough doubt about the safety of vaccination that many parents are choosing to forgo having their children immunized.
This state of affairs has already had dire consequences. According to an article by Dr. Harriet Hall in Skeptic magazine and an article on the BBC News website, in the UK alone measles cases have risen from 56 in 1998 to 1348 in 2008, and at least two children have died, as well as three in Ireland. Tragically, says Dr. Hall, the fear of unsafe vaccines is based on nothing but discredited research, misunderstandings of data, conspiracy theories and sensationalized media accounts.
The MMR-Autism Connection?
As Dr. Hall discusses in her Skeptic magazine article, until 1998, hardly anyone questioned the safety or efficacy of the MMR (measles, mumps, rubella) vaccine, and it was routinely given to children both as toddlers and before starting kindergarten. But in that year, a paper appeared in the British medical journal The Lancet. Its principal author, Dr. Andrew Wakefield, thought he had stumbled upon a link between autism and intestinal inflammation, though his initial sample size was only twelve children, ten of whom were autistic. The purported MMR connection came about after parents of eight of the autistic children claimed they had noticed symptoms of autism only after the children had received the MMR vaccine.
Dr. Hall writes that Wakefield was apparently convinced by these anecdotes, for even though his published paper explicitly stated that no connection between the MMR vaccine and autism had been proven, he held a press conference shortly after the paper appeared and said the exact opposite — that the vaccine probably did cause autism. He did not advocate forgoing immunization altogether, though he recommended receiving the three vaccines separately, with a year between each injection. Since the MMR was not available in its component parts, fearful members of the public, after hearing Wakefield’s opinions in the media, decided to skip immunization entirely.
Andrew Wakefield Discredited
There were several problems with Wakefield’s autism study, as discussed in several books and articles, notably Paul Offit's Autism's False Prophets and Michael Specter's Denialism.
Firstly, there was no control group with which to compare the rate of intestinal inflammation in autistics and non-autistics. Secondly, the MMR aspect only became an issue after some parents made anecdotal claims, and was never properly tested. Thirdly, Wakefield’s results were unable to be replicated by other researchers. In addition, ten of the thirteen initial authors of the study withdrew their names, and The Lancet eventually retracted the paper.
It was later alleged by journalist Brian Deer that Dr. Wakefield had many conflicts of interest he had failed to divulge. According to Deer, Wakefield had applied for a patent on his own measles vaccine, for example, and he had taken money from a lawyer who was working on a class-action suit against MMR manufacturers that claimed the vaccine caused autism. Eleven of the twelve children in the original study were involved in the lawsuit.
Because of these irregularities, as well as several other discredited and sometimes allegedly unethical studies he had worked on, Wakefield was charged with "serious professional misconduct" by the General Medical Council in the UK, though he has denied the charges. According to their website, the GMC will be considering his case beginning on November 19, 2009. Meanwhile, Wakefield has been working at an autism clinic in the US and continues to spread his theories.
Mercury/Thimerosal
At around the time of Wakefield’s original paper, there were also rumblings in the US that the presence of thimerosal in vaccines was causing various neurological disorders, particularly autism. The FDA, responding to public concerns and demands for ever safer vaccines, decided to remove thimerosal from some vaccines in 1999, though they explicitly state on their website that fears of the dangers of thimerosal are unwarranted. Thimerosal, a preservative that is used to allow vaccines to be stored in multi-dose vials, does contain a small amount of ethyl mercury, but this amount was well within EPA guidelines, which in any case are based upon the more dangerous methyl mercury. The tiny amount of ethyl mercury present in vaccines had been shown in several human and animal studies to be safe; indeed, a 1929 study in which people were injected with 10,000 times the thimerosal used in modern vaccines showed no adverse effect, as Dr. Harriet Hall discussed in her Skeptic article.
As Paul Offit writes, the dangers of the thimerosal scare are evident in the growing number of cases where parents subject their children to what some call quack treatments like mercury-chelation and drug-based testosterone suppression in order to “cleanse” the mercury from their bodies. But as with the supposed link between MMR and autism, there is no evidence to support the contention that thimerosal is harmful or that it causes autism; diagnosed cases of autism, in fact, have been increasing in the decade since thimerosal was removed from vaccines.
Immunization Fears
Far from winding down, the initial panics about MMR and thimerosal have only escalated and expanded to encompass all vaccines. Paul Offit, in his book Autism's False Prophets, points out that anti-vax activists have jumped on many other vaccine ingredients that are either present in safe quantities — like formaldehyde or aluminum — or not present at all, like antifreeze or aborted fetuses. Sensationalistic media warnings and celebrity endorsements — notably from actors Jenny McCarthy and Jim Carrey — have fuelled the fire. Despite anti-vaxers claims that they are only trying to make vaccines safer, they have, according to many critics, ironically imperiled public safety by allowing once-controlled diseases to gain a foothold among unvaccinated children, as Fox News reported happened in July 2008, with measles outbreaks in 15 US states. As the CDC and many other pro-vaccine organizations have pointed out, If large segments of the population are not immunized, “herd immunity” will be compromised, and more outbreaks and deaths may be inevitable.
Sources:
Hall, Harriet. "Vaccines and Autism: A Deadly Manufactroversy." Skeptic. Vol. 15 #2 2009: 26-32.
Offit, Paul A. (2008). Autism’s False Prophets: Bad Science, Risky Medicine, and the Search for a Cure. Columbia University Press. ISBN: 0231146361.
Specter, Michael (2009). Denialism: How Irrational Thinking Hinders Scientific Progress, Harms the Planet, and Threatens Our Lives. The Penguin Press HC. ISBN: 1594202303.
"CDC: Measles outbreak linked to lack of vaccinations." Available at: http://www.cnn.com/2008/HEALTH/conditions/05/01/measles.outbreak/index.html. Seen 9 November 2009.
"UK 'in grip of measles outbreak.'" Available at: http://news.bbc.co.uk/2/hi/5081286.stm. Seen 9 November 2009.
"Measles Outbreak Spreads to 15 States, Largest in 10 Years." Available at: www.foxnews.com/story/0,2933,379388,00.html. Seen 4 November 2009.
United States. FDA. Vaccines, Blood & Biologics. 1 Sept. 2009. Seen 9 Nov. 2009 <http://www.fda.gov/biologicsbloodvaccines/safetyavailability/vaccinesafety/ucm096228#t3>.
"Fitness to Practise Panels & Investigation Committee hearings week commencing 23 November 2009." Available at: http://www.gmc-uk.org/news/4129.asp. Seen 11 November 2009.
 |
