Bird Flu and Turkeys

It's not just Suffolk and the 150 000 turkeys.

Nigeria and Japan have recently reported a series of cases of the lethal H5N1 virus. Russia, South Korea, China, Egypt, and Vietnam have also revealed outbreaks in birds and in humans in the past two months.

Jo Revill, the Observer's health editor, has a good article today:

The great fear is that the [H5N1] 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.

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.

The problems are, one, in Britain alone, that's 15 million people with flu (mass societal disruption), and two, until the actual flu pandemic occurs, scientists won't be able to fashion a vaccine specific to whatever mutated strain of H5N1 is fuelling it. Tamiflu is the current drug recommended for first-responders, but recent Egyptian cases indicate that tamiflu-resistant strains are already developing.