This week's Herald column from yours truly looks at the fears and fearmongering concerning the H1N1 vaccine and vaccines in general:
It should strike us as very telling that many of those complaining of unnecessary and unjustified fears over H1N1 flu are the same one spreading unnecessary and unjustified fears over the H1N1 vaccine.
The blatant hypocrisy of engaging in one form of hysteria while denouncing another belies a deeper agenda: vaccine denial.
The scope and severity of H1N1 may indeed have been overblown to some extent, although we've not yet really seen what this new virus is capable of. Fortunately, thanks to science and medicine, we need not witness its full potential.
Also, some of the alarmist rhetoric and sensationalist reporting has fostered a high level of public cynicism - an atmosphere which has provided fertile ground for the anti-vaccine movement.
On top of that, there's the perception that this the flu, after all, which for the most part is unpleasant but not the end of the world. Most H1N1 cases have been relatively mild, so it may seem more of an inconvenience for people to get a shot: apathy as opposed to fear.
When you couple that with the ramping up of anti-vaccine rhetoric, though, it's little surprise that some polls show a majority - or near-majority - of Canadians saying they will not get vaccinated.
But even if you are at worst going to contract a minor case of H1N1 flu, what if you then pass it on to someone at much greater risk of complications? Moreover, H1N1 seems to pose more risk to healthy young women and men than does seasonal flu.
Reducing the total number of cases of H1N1 flu is achievable and desirable - what's the upside of mass vaccine refusal?
There's some understandable concern among Canada's medical establishment, which is why Canada's chief public health officer has gone out of his way to counter the myths and make sure we're all aware of the facts.
Dr. David Butler-Jones is saying what the vast majority of other top medical experts are saying: the H1N1 vaccine is safe and effective. The benefits of getting it far outweigh the risk of refusing it.
Flu vaccines are not perfect, but their efficacy and safety have been demonstrated over and over again in the peer-reviewed medical research. Yet that matters little to the true believers of the anti-vaccine movement who routinely denounce even our most proven and effective vaccines.
(...)All the anti-government and anti-corporate rhetoric in the world is no substitute for scientific evidence.
In this respect, the anti-vaccine movement comes to resemble creationists: with no science or evidence to bolster their argument, they run around trying to poke holes in the mountain of evidence bolstering the case of that for which they are in denial.
Mind you, creationism never gave anyone the flu, measles, or polio.
Fear the quacks. Fear the conspiracy theories. Fear not the flu shot.
Further reading here, here, here, here, here, and here. Also, a caller last night asked me about the concern over Guillain-Barré syndrome and an outbreak believed to be linked to the 1976 swine flu vaccine. Here's the article in New Scientist magazine I mentioned:
In 1976, after the death of a US army recruit triggered fears of a repeat of the deadly 1918 pandemic, around 48 million Americans were given a swine flu vaccine. Of these, 532 developed Guillain-Barré syndrome, a paralytic condition caused by rogue antibodies attacking nerve cells. Most people recover from Guillain-Barré, but not all; 25 died after 1976 and others suffered lasting damage.
The 1976 vaccine caused around 10 cases per million vaccinated. Even ordinary flu vaccines, however, are thought to cause one extra case of Guillain-Barré per million, in addition to the 10 to 20 per million who get Guillain-Barré some other way every year.
Does this mean it is safer not getting vaccinated? Absolutely not. First, there is the risk of swine flu killing you. Second, what few people know is that flu itself is far more likely to cause Guillain-Barré than any flu vaccine.
A 2009 study found that out of every million people who get flu, between 40 and 70 develop Guillain-Barré. So your best chance of avoiding Guillain-Barré is to get vaccinated, a conclusion backed by a 2007 study.
The vaccine risk is also diminishing. Cases of Guillain-Barré in the US have fallen 20 per cent since 1996, and cases reported after flu vaccination have fallen by 60 per cent. Intriguingly, this coincides with a fall in infections by the food poisoning bacterium Campylobacter, thanks to improved meat hygiene. Guillain-Barré usually follows infections, and Campylobacter is the main cause. It is also endemic among chickens, and flu vaccines are grown in chicken eggs. So the occasional contamination of flu vaccines with Campylobacter proteins might explain the link with Guillain-Barré, according to a 2004 study.
That is reassuring, if true. If the problem in 1976 was contamination rather than some property of the virus, there is no reason to expect a repeat. There has never been a similar problem with any other vaccine. And almost all the pandemic vaccines now being given in the US, the UK and Australia are being made in the same plants and in the same way as ordinary flu vaccines.
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