One of the ways of detecting you’ve entered a scare campaign domain, is that you suddenly become stupid. You are just getting along swimmingly and all of a sudden you will either get the strange feeling, ‘oh, this looks like something I should have known’ or you will be told directly, ‘you ought to have known this!’. Or, even laughed at: ‘you don’t know this?.
The second feature is, you’ll find yourself in the presence of fake experts. I know the warmers have preemptively cornered this explanation as though it works in their favor but we’ll ignore it for now. When a strong orthodox line is made accessible and attractive, it becomes easy for noisy busybodies to speak with authority, whereas under normal circumstances, only genuine experts and knowledgeable amateurs would be moved open their mouths. Good examples are Keith Kloor and John Cook, a journalist and a cartoonist, respectively, bloviating on vaccines, and Mark Hoofnagle spreading pronouncements on ‘denialism’. There are numerous others.
Examine in this light a recent article by Peter Doshi in the British Medical Journal. The introduction characterizes how the influenza vaccine is currently presented:
Today around 135 million doses of influenza vaccine annually enter the US market, with vaccinations administered in drug stores, supermarkets—even some drive-throughs. This enormous growth has not been fueled by popular demand but instead by a public health campaign that delivers a straightforward, who-in-their-right-mind-could-possibly-disagree message: influenza is a serious disease, we are all at risk of complications from influenza, the flu shot is virtually risk free, and vaccination saves lives.
But, Doshi says, the real situation is different:
Closer examination of influenza vaccine policies shows that although proponents employ the rhetoric of science, the studies underlying the policy are often of low quality, and do not substantiate officials’ claims. The vaccine might be less beneficial and less safe than has been claimed, and the threat of influenza appears overstated.
The evidence on benefit from influenza vaccination in reduction in elderly deaths is non-existent. This is observational studies in such journals as The New England Journal of Medicine notwithstanding, where high figures for percent reduction in mortality from vaccination (mindbogglingly at 27-50%) have been published.
Though known for a while, Doshi summarizes how these high numbers are the product of bad statistical inference making, owing to the healthy bias effect. Of course, if you had asked questions about it, you will be given the ‘you-must-be-crazy’ look.
Remember again, the main reason influenza vaccination came into practice is protection of the elderly and children. Influenza mortality can strike any age group (the 1918 epidemic is a good example, though infected individuals likely died owing to an immune overreaction that is not usually seen). The extremes of age, however, are more commonly affected in serious or potentially fatal disease. This is where the evidence is weak.
Now, where have we come across similar situations before?
[minor edits]: 10/2/2015