Scientists investigating an influenza virus which killed millions shortly after the First World War have found vital clues in the bodies of victims frozen in Arctic ice.

The researchers have found that the deadly virus, known as "Spanish Flu", is vulnerable to modern anti-viral treatments.

Lung tissue exhumed from a body found on the Alaskan dig

They are hoping that examining fragments of the virus genes preserved by the low temperatures will help them prepare for new pandemic infections.

The results of two studies into the genetic structure of the virus were revealed at a meeting of virologists in London on Tuesday.

The viruses were isolated from the bodies of six young coal miners who died during the 1918 pandemic, and were buried on the Norwegian island of Spitzbergen.

Because the corpses were buried in the "permafrost" - ground that is frozen even at the height of the Arctic summer - tissue samples from the brain, kidney, lungs and spleen were well preserved.

Influenza RNA, or genetic code, was extracted, and found to more closely resemble avian (bird) flu than human flu.

But the gene targeted by a new class of anti-flu drugs is present in the 1918 flu, suggesting modern treatments might have been effective against it.

Professor John Oxford, a leading UK virologist, said: "Finding genetic material in these samples is a real step forward in allowing us to decipher the genetic information of the virus.

"We hope to get a genetic picture of this very deadly form of the influenza virus against which we can compare present day flu strains.

"This may alert us to the emergence of strains that have the potential to pose similar risks to health as the 1918 virus and develop treatments and preventative measures, such as vaccines, to avoid such devastation and loss of life."

Another project, from the US Armed Forces Institute of Pathology, managed to sequence an influenza gene after recovering the body of an Inuit flu victim buried in Alaskan tundra.

Fragments of genetic material recovered from tissue samples from two US servicemen were also used.

Although outbreaks of influenza are a regular occurrence in the UK, and are wholly or partly responsible for approximatley 3,000 to 4,000 deaths a year, the majority of strains cannot seriously affect healthy adults.

The influenza virus is constantly mutating, with new strains emerging every year.

Scientists are on the lookout for more virulent varieties, particularly those which appear to have crossed the species divide from animals to humans, as these may be more dangerous.

A recent case of flu in Hong Kong, involving a 10-year-old girl, appeared to have jumped from pigs.

Another Hong Kong outbreak, involving a strain believed to have jumped from chickens, killed several people and prompted the slaughter of thousands of birds in an attempt to eradicate it.

Tracking the victims

The expedition to Spitzbergen which recovered the tissue samples combined detailed detective work with science.

The bodies were eventually tracked down using entries in the diaries kept by a coal company's head engineer, which recorded the names, birth dates and dates of death for the seven miners.

The writings revealed that the virus had reached Spitzbergen on a supply ship in September 1918, bringing farmers and fishermen to work in the coalmines during the winter months.