Nothing seems more medieval than the arrival of an invisible plague spreading across the globe, particularly one which seems to defeat the best medical and industrial efforts.
Yet in terms of human health, the risk is no greater today than it was yesterday. The Suffolk outbreak brings home to us the threat of these influenzas, but the real danger lies abroad. What we have seen in the Far East is how deadly the virus can be if the right biosecurity measures aren't brought in to separate birds from humans. In Indonesia, where the government has failed to cull infected poultry, we have seen 63 human deaths. It was only yesterday that it announced a ban on people keeping domestic poultry.
The great fear is that the virus will jump into a person and mutate, changing its genetic make-up so that it becomes transmissible between species, and then between humans. This could happen in one event, or it could happen gradually. Flu viruses are masters of disguise and can mutate thousands of times until they find a form which gives them a kind of pathogenic immortality.
Every time the virus enters a human being, it's a roll of the dice as to whether it will become a very contagious form. These particles are easily destroyed by heat or even stomach juices, but unfortunately are adept at unlocking the cells lining the respiratory tract, and then trashing them. The body mounts a massive immune response that in some cases is deadly. That's what has caused 162 deaths so far across the globe.
It is important to get things into perspective. During any pandemic, around 25 per cent to 30 per cent of the population would be infected, but the vast majority of people would simply suffer a nasty dose of flu and survive - and then carry immunity to the disease. As the virus mutates, it becomes less lethal, but the unanswerable question is what the overall mortality rate would be.
Over the past week, I've been taking part in an emergency exercise to see how well the UK could cope. As I reported two weeks ago, the government is introducing a 'buddies system', so friends or relatives would be asked to pick up the antiviral medication for the sick. But what if we choose not to act as buddies? The supermarkets are already looking at introducing 'ration packs' as they know how quickly we panic.
But even if we all act sensibly, the lack of any vaccine for up to the first six months of a future flu pandemic would force doctors to make agonising choices. There are key ethical questions to be asked. Turkeys in Suffolk today will become a virulent flu virus tomorrow, and there's a choice: either you panic, or think quietly about how you would act in an emergency, and if you would help those around you.
