Plans to double Britain’s emergency stockpile of flu drugs have been made by health ministers after they accepted that too few drugs have been ordered to contain a devastating pandemic, The Times has learnt.

The Department of Health has asked the Treasury for £150 million to buy at least 15 million extra doses of Tamiflu, the antiviral drug that is the main line of defence against the virus, under a review of its pandemic preparations.

It is also considering ordering vaccines against H5N1 avian flu to cover everyone, at a cost of up to £1 billion.

The revised proposals come after statements by scientists that the existing stockpile of 14.6 million doses of Tamiflu will not allow preventive therapy, the most effective way of saving lives.

A flu pandemic could infect up to half the population and kill up to 750,000 people, according to Government estimates, but giving antivirals to everyone in infected households could reduce both figures by 40 to 50 per cent.

There are currently enough drugs for a quarter of the population, but the latest draft of the Government’s pandemic plan asks hospitals to prepare for a 50 per cent infection rate.

Proposals to “at least double” the stockpile have now been agreed by Patricia Hewitt, the Health Secretary, a senior Government adviser told The Times.

The Treasury has yet to clear the order, but is understood to be sympathetic.

With 30 million doses available, Tamiflu could be given to everybody living in the same home as an infected patient, assuming an attack rate of about 25 per cent. Enough drugs would be available also to treat every clinical case for attack rates of up to 50 per cent.

This would be supplemented by a stockpile of new vaccines against the H5N1 avian virus, which has infected 291 people and killed 172.

The vaccines, made by GlaxoSmithKline and Baxter, are still experimental, and while research is said to be encouraging, there are no published studies showing them to be effective. They also have a shelf life of just three years, and a pandemic is unlikely in that time.

Some officials and scientists are concerned that if a pandemic does not occur and the vaccines have to be thrown away, the Treasury might refuse to spend similar sums on better vaccines in the future.They support a smaller order of 10 to 20 million doses to cover key workers, and also children.

The case for a larger Tamiflu stockpile has won increasing support from scientists since a study led by Professor Neil Ferguson of Imperial College London found last year that Britain ideally needs to have at least 30 million doses on hand.

The contingency plan published in 2005 assumed an infection rate of between 10 and 20 per cent, and the 14.6 million doses of Tamiflu were ordered accordingly. A consultation document sent to NHS trusts and other interested parties, however, now says: “Response plans should recognise the possibility of a clinical attack rate of up to 50 per cent in a single-wave pandemic.”

Professor John Oxford, a virologist at Queen Mary, University of London, said: “All the scientific advice is that this is the way to go. I would be pleased if they ordered the vaccines, though enough to cover a quarter of the population would be about right at the moment.”

Preventing a pandemic

—Tamiflu is the brand name for oseltamivir, an antiviral treatment for strains including H5N1. It is not a vaccine

— It belongs to a class known as neuraminidase inhibitors, which stop virus replicating

— Treatment must start within two days of symptoms appearing. Studies suggest it stops 89 per cent of those exposed to flu from falling ill

— Side effects include nausea and vomiting. There are also concerns that it could induce hallucinations. It has been linked to deaths from falls in Japan

— Developed by Gilead Sciences, a biotechnology company, and manufactured by Roche, it normally costs £16.36 for a course

Source: Roche/Times database

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