Tenpenny’s vaccine advice is worth ten a penny and is certainly a dime a dozen

By Helen Petousis Harris 08/01/2015

Sherri Tenpenny is an American anti-vaccination protagonist causing some disturbance across the ditch, and somehow this issue has crawled into the NZ Herald.  Australian lobby group Stop the Australian Anti Vaccination Network would like to see Sherri’s visa declined so that she may not spread her gospel in their country (The AntiAVN exist to hold the anti vaxers accountable for their dangerous information).

Great to see such strength in the AntiAVN, but in this case I really don’t think denying her a visa is a very good idea – free speech and all that, it is likely to make a martyr out of her. Her claims are so pedestrian they would probably fall relatively horizontal without the extra attention. I sincerely hope the strategy does not boomerang.

Just one of Tenpenny’s ‘facts’ is cited in the news article and it is begging to be addressed. She is quoted:

“Fact: 1 in 50 = Autism Overall, Fact: 1 in 25,000 = Unvaccinated, Prove Me Wrong”.

Fact: Her statement has a factual fallacy and logical fallacies, all wrapped up in about 14 words. Here is why.

  • Firstly, the shifting of the burden of proof –  Sherri has decided she does need not need to prove her claim, rather she has shifted the onus onto others to prove her wrong. Otherwise known as onus probandi. This is not considered valid reasoning; it is argument from ignorance or evidence to the contrary.
  • Secondly the old  Red Herring – US data suggests autism spectrum disorder rates range between 4.8 – 21.2 per 1000 children aged 8 years and this has been rising. I can accept 1 in 50 is a generally accurate estimate. Here is the CDC report. So this is generally true but it is also unrelated to the argument that vaccines cause autism.
  • Thirdly a False statement – That 1 in 25,000 are unvaccinated… Mmmm. This bit looks dubious. Firstly, how many completely unvaccinated 8 year old children are there in the US in order for this comparison to be carried out? Where did this estimate come from?  I presume Tenpenny is trying to say that pretty much all autism is in vaccinated children, of course almost all children the US are at least partially vaccinated. Scientific studies on the matter – of which there are many, find the same risk for Autistic Spectrum Disorder (ASD), which includes autism,  regardless of vaccine status.  For example a recent evidence based meta-analysis found no relationship between vaccination and autism and the Odds Ratio for this was 0.99; 95% CI:0.92 – 1.06) which means to different in risk between vaccinated and unvaccinated.  In other words about 2% of vaccinated and 2% of unvaccinated children may develop ASD. I would be interested to see where this ‘1 in 25,000’ fable has come from; I can find no source other that anti vax claims.

Inconvenient fact – as the number of unvaccinated children increases, so does the prevalence of ASD.

As I write this Tenpenny’s gigs are being cancelled, first Sydney, now Melbourne. Well done Australia for not putting up with a public health nuisance.

0 Responses to “Tenpenny’s vaccine advice is worth ten a penny and is certainly a dime a dozen”

  • interesting stuff- I wonder if she’ll make it across the ditch to here instead?

  • Why do you always revert to emotive and insulting remarks. Are you not concerned that some of your comments could be deemed slanderous to the individuals you appear to actively target. This does little for your profession or your credibility. You have not responded to my email or my comment, which is your right, however, this leaves me wondering why.

    • Do you have a question that is not purely rhetorical?

  • ” Are you not concerned that some of your comments could be deemed slanderous to the individuals you appear to actively target”

    It isn’t slander if it is true, which it is.. demonstrably so. Anything else to have a cry about?

  • My lack of a question mark, was an error. The question was not rhetorical. Scott, by using the phrase “anything else to cry about,” are you attempting to belittle an opinion you do not share? Why do you feel the need to do this? I do not feel belittled by your remark. We perhaps, should beg to differ.