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At Respectful Insolence, Orac has a recent post discussing ‘anti-science’, and I thought of this when I finally got around to writing this piece (which Grant has kindly ‘left to me’, as it were!). Here’s how Orac defines the term ‘anti-science’:

It’s an imperfect term for people who reject well-established science. To get a flavor of what being “anti-science” means, take a look at people who reject evolution, reject anthropogenic global warming, reject vaccines, and reject scientific medicine in favor of quackery.

Which is a reasonable characterisation of some of the content from the IAS website that Grant’s deconstructed, leaving this bit for me (because I asked nicely):

When a well meaning friend or relative questions your decision [not to vaccinate], simply say “I fail to see how injecting heavy metals, foreign proteins, multiple viruses and many toxic substances into a body all at one time can keep someone well, can you explain it to me?”

“Heavy metals”: could they mean (gasp!) mercury? It’s hard to tell, with such a non-specific term. But if they do mean mercury, then this phrase can only be construed as intending to mislead: mercury (as thiomersal) was phased out of New Zealand’s paediatric vaccines in 2000. In reality, the “heavy metals” actually include some elements that are required for life (such as iron, molybdenum, & cobalt) as well as the harmful ones like lead & plutonium – and mercury.

Dose & chemistry also matter. When childhood vaccines in NZ did have thiomersal in them, the mercury was in the form of the organic compound ethylmercury. Unlike methylmercury, ethylmercury has a half-life in the body of around 7-10 days: it is converted to an inorganic form & then excreted. As for dosage, back when our vaccines contained ethylmercury, a 6-month-old child who had received all recommended vaccines would have received a grand total of 175 micrograms of this substance, well below World Health Organisation guidelines.

‘Foreign proteins”? Which ‘foreign’ proteins are we discussing here? Presumably it’s the antigens included in vaccines to elicit an immune response. Which are no more, & no less, ‘foreign’ than the self-same proteins on the surface of a bacterium or the coat of a viral particle. In any case, it’s worth remembering that proteins & large polypeptides from food can cross the gut wall to circulate in the bloodstream, & they’re equally ‘foreign’.

“Multiple viruses”? It’s correct that some vaccines contain viruses. “Live” vaccines contain viruses that are attenuated but which stimulate an immune response in the host. Examples are measles, mumps, rubella, & chickenpox. “Inactivated” viral vaccines (eg for polio & influenza) have had their ability to replicate destroyed – this further reduces the extremely small risk of a “live” vaccine inducing disease, but requires much higher doses to elicit the same immune response. There are also vaccines based solely on viral protein subunits.

Let’s assume that the IAS’s “multiple viruses” refers to the MMR vaccine. Three viruses at once – sounds bad! However, viruses are extremely common in many indoor environments, so daily exposure to viral particles may be many orders of magnitude greater than the 3 in that particular vaccination. Many pathogenic viruses are airborne, entering the body through mucous membranes, and some can persist for up to several months on dry surfaces. Overall, an individual’s daily exposure to antigens is many orders of magnitude greater than exposure via vaccines.

As for the “many toxic substances” part (oh noes, teh ebil toxins!) – it’s notable that many of those who cite the presence of toxins appear quite unable to identify what they are. The term ‘toxins’ is presumably sufficiently scary to put hearers off asking for elucidation. At a guess, IAS might be referring to formalin, squalene, & or aluminium. However, once more dose is important. None of these are toxic at the concentrations found in vaccines – in the case of aluminium daily exposure through food & drink is far higher (hardly surprising when you consider that it’s one of the most abundant elements in the earth’s crust). And our bodies make both formalin (formaldehyde) & squalene as part of their normal metabolic functioning.

So, sad to say, that particular anti-vaccine website could fairly be characterised as anti-science.