FLU vaccines may be far less effective at combating seasonal outbreaks than previously thought, researchers say, adding that they may not be worth the cost and effort required to produce them.

According to a review published today, there is little clinical evidence that the vaccines reduce deaths significantly, hospital stays and time off work among those most at risk from seasonal flu, including the over-65s and those with chronic heart and lung conditions.

Public policy worldwide recommends the use of inactivated influenza vaccines — those that contain dead viruses and are given with a needle in the arm — to prevent outbreaks. More than 15 million doses of vaccine have been ordered for use this winter in Britain.

But according to Tom Jefferson, a vaccines expert, vaccines given to children under 2 have the same effect as if they were given a dummy drug. He is calling for an urgent re-evaluation of vaccination campaigns.

Writing in the British Medical Journal, he says that because influenza viruses mutate and vary from year to year, it is difficult for scientists to study the precise effects of vaccines and that most existing studies are of poor quality.

Responding to Dr Jefferson’s comments, David Salisbury, director of immunisation at the Department of Health, said: “In older people, protection against infection may be less, but there is good evidence showing that immunisation reduces broncho- pneumonia, hospital admissions and mortality.”

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