Thankfully, the antivaccination lobby is (so far!) relatively small & quiet in New Zealand. It's another story in the US, where various celebrities lend their names to the anti- voices. A couple of days ago Orac posted another in his series on what's wrong with the US anti-vax groupings, & I thought I'd talk about some of the issues he highlights - they need to be made here too.
One argument against the vaccination schedule is that it represents too many antigens, too soon, & so children's immune systems are simply unable to cope. This is plain silly - we are all exposed, every day, to a very large number of potential antigens (molecules that provoke an immune response). And unless someone is severely immuno-compromised, their immune system deals with those challenges with no difficulty.
A second anti-statement is that we don't need vaccines, and that your immune system can somehow be 'boosted' by attention to diet or by taking supplements. But again - most folks' immune systems work fine on their own, & in fact, I'd be a tad cautious about taking steps to ramp it up, given that autoimmune diseases seem to be due to an immune system that's looking around for something to target.
Until recently, arguments in the US centred on the presence of thimerosal, a mercury compound, in many vaccines. (It's actually been absent from vaccines for some years now, but acted as a preservative.) High exposure to some forms of mercury is known to cause neurological damage - think Minamata disease. (Or think of the Mad Hatter in Alice in Wonderland: mercury was used in the process of making felt for hats.) This was extrapolated to claims that the thimerosal in childhood vaccines was linked to autism - but after many thorough studies there's no evidence to support those claims.
Anyway, the focus has now moved to 'toxins' (a suitably vague term), including formaldehyde. Which is indeed found in some vaccines, as an adjuvant. But - & it's a big 'but' - formaldehyde is produced in your body as a normal metabolic by-product, regularly & at levels higher than those found in any vaccine. What's more, it's released into the air by a range of industrial processes, and also by many household products & building materials. It would be surprising if the tiny amount in vaccines made any difference at all to that normal exposure.
Which links to my final talking point for the day - the idea that 'chemicals' are bad & 'natural' substances are good. This one really bugs me: for a start, we're all made of 'chemicals'. Water is a chemical (and much fun can be had by calling it 'dihydrogen monoxide', which somehow makes it sound like a Bad Thing). So is the atmospheric component that we require for cellular respiration: oxygen.
Maybe what's meant in this claim is that 'man-made' chemicals should be avoided, but 'natural' is OK. Hmmm. Tell that to the family of Georgi Markov, assassinated using a pellet of the poison ricin, derived from castor oil beans. Or to someone who's consumed fugu (made from pufferfish) prepared by an unskilled chef. Or what about botulinus toxin? It's produced by bacteria, so definitely 'natural'. But consume enough of it - & 'enough' is a very small quantity indeed (about 1 nanogram per kg bodyweight) - & you'll die a rather unpleasant death. Of course, as for many things dosage is important, & where would the purveyors of botox be if that wasn't the case?
Much about our world is neither simple, nor intuitive. But doesn't that make it a more interesting place? You just need to keep asking questions :-)