Scientists warn of new form of bird flu virus epidemic
Pastor Dale Morgan
Scientists warn of _new form of bird flu virus_ epidemic*
By Andy Bloxham
Last Updated: 7:00AM BST 27/05/2008
A strain of bird flu has moved a step closer to developing the traits
required to create an epidemic of the disease in humans, scientists
warned on Monday.
Researchers who analysed samples of recent avian flu viruses found that
a strain of the virus called H7N2 had adapted slightly better to living
in mammals.
Tests on ferrets proved the strain could be passed between animals but
scientists said the evidence suggested that bird flu could be
transmitted between humans.
Dr Terrence Tumpey, a microbiologist with the US Centers for Disease
Control and Prevention, in Atlanta, Georgia, said: "The finding
underscores the necessity for continued surveillance and study of these
viruses as they continue to resemble viruses with pandemic potential."
The virus tested on the ferrets - a standard animal model of flu in
humans - was isolated from a man in New York in 2003, where it thrived
on the same sugars found in the human windpipe.
The scientists said the virus could be evolving toward the same strong
sugar-binding properties of the three worldwide viral pandemics in 1918,
1957 and 1968.
Like H5N1, the H7 family of flu viruses also primarily affects birds.
A deadly version of the H7N7 strain hit poultry in the Netherlands in
2003, and a less severe form, H7N2, broke out in the UK last year.
Some have estimated the death toll of an avian flu pandemic could be 100
million, including 500,000 in Britain.
The World Bank estimates that the financial cost of a pandemic could
exceed $2 trillion.
The study appeared in the journal Proceedings of the National Academy of
Sciences.