Anti-flu drugs could prevent patients with influenza from contracting life-threatening pneumonia, scientists have suggested.

Laboratory tests on a new antiviral drug have found that it not only reduces the impact of a strain of flu known as influenza A, but also cuts the risk of further complications, including pneumonia.

The drug called Tamiflu (oseltamivir phosphate) is licensed for use in the US but has yet to be approved by authorities in the UK.

There is some way to go before we can say that this will be the case in patients

Professor Malcolm Green, British Lung Foundation

Experts said the findings could be significant if the laboratory results could be repeated in humans.

Scientists from the University of Kansas Medical Center studied the link between Streptococcus pneumonias and the influenza A virus.

They found that the pneumonia bacteria spread more quickly in those cells that had already been infected with influenza compared with those that did not have the virus.

Reduce infection

However, treating the cells with Tamiflu was found to reduce the increased rate of pneumonia infection.

The authors said the findings suggested that the drug might "perhaps prevent post-influenza complications, such as pneumonia".

The findings of the study, which was funded by Tamiflu manufacturer F. Hoffman-La Roche, were presented at the annual general meeting of the American Society for Microbiology in Salt Lake City on Wednesday.

Professor Malcolm Green, vice-president of the British Lung Foundation, described the study as "very interesting".

"It looks as if treating the influenza virus with Tamiflu helps to prevent Streptococcus pneumonias coming on board."

But he added: "It is a very interesting laboratory study but there is some way to go before we can say that this will be the case in patients."