Leading article: This abuse of Tamiflu is dangerous for all of us

We risk undermining our collective ability to cope with swine flu

Our report today revealing that tens of thousands more people are likely to have received the antiviral drug Tamiflu than actually have swine flu should be a cause for concern for both the health authorities and also the wider public. This over-prescription is obviously a waste of National Health Service resources. But more damaging are the potential medical and social costs of a large number of people taking the antiviral drug when they show no symptoms of the illness.

Tamiflu is not, of course, a cure for swine flu. The drug inhibits the spread of the virus through the body and makes it less likely that the patient will transmit it to others. While we wait for a vaccine to be developed, it is one of our few defences against its spread.

Medical researchers have long warned of the danger that the mass prescription of antivirals could result in the swine flu virus becoming resistant to the drugs. If a large number of people without symptoms take them now we could be weakening our collective ability to deal with a future wave of the swine flu virus.

The risk of new more resistant strains developing is real. Health authorities in Denmark, Japan, Hong Kong and Canada have already reported cases of patients whose swine flu carried a mutation making it impervious to the influence of Tamilfu. It remains to be determined whether these were simply isolated cases, or part of a wider trend. But we do know that excessive use of Tamiflu (and the other main antiviral drug, Relenza) by populations will increase the likelihood of new resistant strains of the virus developing.

The National Pandemic Flu Service hotline launched at the end of last month has facilitated the widespread distribution of the drug here in Britain by allowing people to access it by describing their symptoms to non-medically qualified employees over the phone. Many of those requesting the drug probably believe they have swine flu, even if they are mistaken. Others will be playing the system in order to claim Tamiflu supplies as an insurance against contracting the virus.

There was always a danger that the hotline would be abused when it was set up. The risks of abuse were judged by the authorities to be outweighed by the risks of genuine patients flooding into GPs' surgeries and accelerating the spread of the flu still further. In light of this new evidence, that judgement ought to be revisited. At the very least, the Government needs to inform the public of the dangers of taking Tamiflu pre-emptively. A public advertising campaign highlighting the side-effects (which include nausea, vomiting and insomnia) would be useful.

The latest official figures indicate that the number of swine flu cases in the UK is abating. But there is only a limited amount of comfort we can draw from this trend. Swine flu infection was always expected to die down over the warmer summer months. And there remains a real danger of the virus returning, possibly in a new more virulent form, in the winter.

The 1918 "Spanish Flu" epidemic began mildly, but became progressively more deadly. Our health authorities have learned a great deal since those days. Britain has significant stockpiles of antiviral drugs and progress towards a vaccine is advanced. The challenge now is to prevent the general public – either through selfishness or ignorance – making us more vulnerable than we otherwise would be.