The mutation that makes flu viruses become pandemics may also be their main weakness, researchers revealed last night.
New scientific studies have found a startling similarity between the deadliest ever flu virus, the 1918 virus, and the H1N1 swine flu virus that caused world-wide panic last year.
Scientists said this meant the same antibodies were able to destroy both viruses – an equally surprising finding.
As flu viruses mutate regularly, the human body has to create new defences against each one – leading to the need for vaccines to be changed and up-dated every year.
But the new findings, reported in Science Translational Medicine, suggest the swine flu vaccine would also have worked against the 1918 virus, which killed millions world-wide.
The key is that both viruses lack sugar molecules at the same points on a key protein on the surface of the virus – hemagglutinin.
Scientists say this makes them more able to by-pass human defences – creating pandemics – but ultimately also makes it easier for the body to develop anti-bodies against the virus.
Researcher Dr Gary Nabel, of the US National Institute of Allergy and Infectious Diseases, in Bethesda, Maryland, USA, said it was "surprising" that the same antibodies could combat both viruses.
He said: "This study defines an unexpected similarity between two pandemic-causing strains of influenza.
"It gives us a new understanding of how pandemic viruses evolve into seasonal strains, and, importantly, provides direction for developing vaccines to slow or prevent that transformation."
Science Translational Medicine. DOI: 10.1126/scitranslmed.3000799 (2010).
Leave a Reply