All entries for Monday 05 February 2007
February 05, 2007
Unless you have a policy of avoiding the news entirely, you can’t have failed to notice that “Bird ‘flu” is making headlines again. The highly pathogenic H5N1 strain has been confirmed in turkeys on a farm in Suffolk, which is now being culled out. An awful lot of ink (and electrons) has been spilled already on the subject, so I shall try and be concise! Personally, I’ve been pleased to see that the press have been finding epidemiologists to ask about what’s going on rather than just speculating wildly, which is what we’ve tended to see in the past.
The big question, in my opinion, is where this outbreak came from. The affected unit, like most industrial poultry farms, has tight biosecurity, designed to keep wildlife (rodents and birds) out. Speculative reports have suggested a wild bird got into a ventillation shaft (or managed to excrete virus-laden faeces in precisely the right location), but that seems unlikely to me – it’s not really the time of year for birds to be migrating into Suffolk, and any such bird would still have to get into the unit. The only other option would be imported birds which were infected overseas, but the EU has quite serious restrictions on the import of live birds. DEFRA are pursuing the investigation very seriously, and hopefully we’ll have an answer soon.
The risk to human health isn’t high, though. Granted, this strain does have a high mortality rate in people, but it has, so far, proved difficult to catch. Unless you’re working with poultry, you’re unlikely to be exposed to any great extent. Of course, it might yet mutate into a form that is readily transmissible between people, but it hasn’t yet, and I’m inclined to the opinion that it’s not terribly likely to do so in the near future. It is a matter of chance, though, and the more cases in birds, the more people will get infected, and the more opportunity for such a mutation to take place.
DEFRA will be worried about the possibility of H5N1 getting into the wild bird population, which would be a difficult situation – that would put free-range and other outdoor-reared poultry at risk, and be difficult to eradicate.
For more detail on the subject, see DEFRA’s pages here, which include an advice line, and directions for what to do if you find dead ducks, geese, swans or waders.