Indecision and delay exposes Britons to the full risk of the bird flu virus. Geoffrey Lean reports

Britain will be largely defenceless against a devastating and "imminent" pandemic of bird flu for more than a year, an Independent on Sunday investigation can reveal.

Britain will be largely defenceless against a devastating and "imminent" pandemic of bird flu for more than a year, an Independent on Sunday investigation can reveal.

Stocks of flu-busting drugs, ordered by the Government in a blaze of publicity last week, will take up to two years to build up. Even in a year's time, Britain will have less than half of what it needs. And ministers have dismissed a call from the World Health Organisation (WHO) to stockpile vaccines that might give protection against the worst effects of the disease, which - experts say - could kill 500,000 Britons.

The facts undermine assurances by ministers and top officials last week that Britain was "well prepared" for a pandemic, which the WHO describes as "imminent" and "knocking at our door". The Secretary of State for Health, John Reid, boasted that the announcement of the order for 14.6 million courses of the drug Tamiflu put the country "in the forefront of international preparedness". But, in fact, it is well back in the queue for limited supplies behind other countries - from France to New Zealand - that put their orders in earlier. And it has not yet even joined the queue for vaccines, although countries such as the United States, Italy and France have already taken steps to assure supplies.

Last week's announcement followed weeks of dithering and was hurriedly brought forward following intense press and political pressure. Until about 10 days ago the Department of Health was insisting that it would only make its mind up about ordering the drugs "some time in the spring", despite repeated warnings of increasing danger from international authorities. The WHO warns that "the world is now in the gravest possible danger of a pandemic", while the UN's Food and Agriculture Organisation calls it "a sword of Damocles" hanging over the globe.

A flu pandemic occurs when a new virus, to which no humans are immune, suddenly starts spreading rapidly from person to person. The bird flu - codenamed H5N1 - which is infecting poultry and some people in South-east Asia, has yet to do so, but experts are unanimous that it is only a matter of time. When it does, they expect that it will create the greatest pandemic since the Spanish flu of 1918-19, the world's worst ever disaster (see right), and could even be more devastating. So far, more than 70 per cent of the people known to have caught it have died.

Ministers admit that, once a highly infectious virus emerges, it will "spread rapidly" to Britain, thanks to modern air travel - and that, once it has arrived, it will be impossible to stop it sweeping through the country.

Present flu vaccine offers no protection against it, and a fully effective one cannot be developed until after the emergence of the particular strain that spreads rapidly among people.

Even then, it will take many months to produce enough of it to make a major impact on the pandemic.

In the meantime, the world has two defences. The first are vaccines based on the strain of the flu now infecting chickens. While not giving full protection, these may blunt its effects; they would not stop people catching the flu, but might prevent them dying from it.

Several such vaccines are now being developed, and the WHO has urged governments to consider stockpiling them. The United States has placed an order for four million doses, and Italy and France for two million each.

But the UK Government has refused to follow suit, on the grounds that the perfect vaccine is not yet available. When challenged with the action taken by other countries, it could only offer the response that they would not have been able to place their orders if it had not been for research work done in British laboratories.

The second defence is the anti-viral drug oseltamavir - marketed by the Swiss chemical giant Roche under the name Tamiflu - which has been specifically designed to tackle flus of this general type. Again, it would not stop people catching the disease but the Government admits that there is "impeccable evidence" that it will mitigate its worst effects. Yet for months the Government sat on its hands while other countries such as France, Canada, Australia and Japan ordered it.

Ten days ago New Zealand became the 12th country to put in an order. Like Britain, it ordered enough drugs to cover one-quarter of its population - the WHO's recommendation. Unlike Britain, it is getting them fast; its stocks will be complete by midsummer.

Even Ken Livingstone - who 10 days ago beat the Government by ordering 100,000 courses to cover essential workers in London - will receive his stocks within eight weeks. But the Government says it will only build up Britain's supplies "over the next two financial years", which means that they may not be complete until early April 2007, by which time the pandemic may well have taken place.

It adds that it will have only half of them "available" by April 2006. Roche will not say when it will start delivering the supplies, citing "confidentiality", and the Department of Health says that it does not know.

Andrew Lansley, the Shadow Health Secretary, says that he has been authoritatively informed that the bulk of the first half of the order will not arrive before the end of this year. He said yesterday: "We are well down the queue because we did not get on with it. The Government did not respond to the threat as quickly as it should have done, or as other countries did. As a result, our defences are down for the next 12 months."

THE PANDEMIC OF 1918-19: 50 million dead - how flu stopped the world

By David Randall

On 21 June 1918, there appeared in the New York Times a small item about "a mysterious sickness now prevalent in Spain". Said to emanate from Germany, it was caused by poor diet, in particular the consumption, by a war-stricken people, of large quantities of turnips.

The paragraph was, in almost every respect, wrong. There was, it was true, a sickness - but it had not started in Germany, and it most certainly was not caused by a surfeit of root vegetables. It was flu, and before the following year was out, it would kill about 50 million world-wide, making it the worst disaster in recorded human history.

The papers of the day called it Spanish flu, for that was the country - neutral, and so lacking press censorship - where the disease was first widely reported. But it soon became clear the sickness was not confined to Spain; this was a highly mobile virus. By 4 July, the London Times said the flu was spreading across the UK, and, two days later, chemists were reported to be running out of cinnamon and quinine, two supposed cures. One correspondent suggested that the sick should use snuff instead.

No remedy was any use (flu virus was not isolated until 1933), and so, as the summer wore on, the sickness became an epidemic. Millions died in Spain; France and Germany were badly hit, and, by September, one in four Americans were infected. Things were soon so chronic in London that no fewer than 700 staff at the London central telegraph office were off sick. Come October, the epidemic had become a global contagion, and, in the third week of that month, 4,000 died in a Britain which lacked even a ministry of health, never mind an NHS.

Victims collapsed in the street and died within hours. From America came a report of four women playing bridge one evening, three of whom had contracted the disease and died before daybreak. In Britain, nearly all schools were shut, and, by the end of the month, there were no fewer than 2,225 deaths in London alone.

And so it went on, save for a lull in January, for nearly 18 months. It left 230,000 UK dead, 675,000 in the US, and up to 50 million victims world-wide. One-fifth of the world's population was infected, and the virus turned out to have a mortality rate 25 times that of a normal flu, affecting an unusually high proportion of the young and healthy. Scientists now believe that it originated in the Far East, in birds.