There’s been a lot of ink sneezed recently on how we should organise our response to H5N1 and, latterly, H1N1 – on questions of who should be top of the Tamiflu distribution list and on how the distribution should be organised.  (To give a recent example, Dan Sokol touches on the question here.)

However, one aspect of our policy has possibly been overlooked – that the more prophylactic Tamiflu we distribute, the greater the chances of the virus developing resistance to it, thereby undermining the whole vaccination project.  If reports from Denmark are to be believed, there seems to be some evidence that this is happening:

On 29 June, Denmark’s National Board of Health announced the first known case of H1N1 swine flu resistant to [Tamiflu]. The woman was in contact with an infected person and was put on low-dose Tamiflu as a precaution, but she developed flu anyway.

She has now recovered after taking the antiviral Relenza, and the drug-resistant strain appears not to have spread. The State Serum Institute in Copenhagen assumes resistance emerged during treatment with Tamiflu, as low doses can favour the emergence of resistant strains.

If health authorities continue to hand out prophylactic treatments, further resistant cases are likely to emerge. As many countries have stockpiled Tamiflu, and a specific vaccine is unlikely to be available in time for the next wave of swine flu, this could prove disastrous.

Presumably, there’s a similar risk of the virus developing Relenza resistance, too.  So there seems to be an interesting dilemma generated: while governments presumably ought to take steps to ensure the availability of prophylaxis, this also generates a risk that they’re creating a much bigger problem further down the line.  I don’t think that this is an argument against prophylaxis per se – of course governments should deal with the threat as it stands at the moment (and anything else would be a counsel of despair), and the threat of resistant H1N1may never be realised – but the point would stand that, in doing what they ought to do now, they may be making things worse in the long run.  And that means that meeting the present danger isn’t nearly as morally straightforward as it would seem at first.