- Scientists are urgently trying to determine whether a
killer virus wreaking havoc in the US has arrived in Britain.
-
- Evidence has been found in dead birds of antibodies to
West Nile virus, although no human cases have been detected where the illness
has developed in this country. Doctors had been warned to look out for
unexplained instances of brain inflammation.
-
- Previous cases in Britain have been identified only among
travellers, although most people who get it do not even display symptoms.
The chief medical officer, Sir Liam Donaldson, warned earlier this year
that the virus might become a threat, even though official estimates had
described the risk as low.
-
- He is coordinating meetings on how an outbreak might
be tackled, but it is still unclear whether the birds in the study had
the active virus, caught from mosquitos, or had merely developed antibodies
while migrating to infected areas or mixing with birds travelling from
these areas.
-
- The Department of Health said: "Public health officials
and the department have been considering whether West Nile virus poses
a risk of infection in this country. We will need to consider the implications
of this study of bird populations once it is published."
-
- The disease has claimed 188 lives in the US this year,
mostly among people over 50. A further 3,200 people have been identified
with the disease in the past 10 months. The disease, now spreading quickly
through the western hemisphere, has spread to 38 states and Washington
DC since it arrived in New York in 1999. Birds are thought to be the main
hosts for the disease, which is spread by mosquitoes feasting on their
blood. The mosquitoes then infect animals and humans.
-
- The risk of human to human transmission is thought to
be low but there is concern over infected blood used in transfusions. A
handful of such infections have been identified in the US. An infant who
might have been infected through breast-feeding has been reported as having
antibodies but is said still to be healthy .
-
- Officals from the Centres for Disease Control in the
US are in regular contact with public health officials here about the disease.
-
- The alert was raised by scientists at the Oxford-based
Centre for Ecology and Hydrology. They plan to announce their findings
in a scientific journal shortly. Limited surveillance of birds has been
under way for about two years but it was hampered by restrictions against
foot and mouth disease.
-
- Doctors have been warned for some time to inform authorities
about unexplained brain inflammation. Samples of blood and fluids have
not indicated any human infection, a point emphasised by the Department
of Health and the public health laboratory service for England and Wales.
-
- The risk of infection has been said to be low, partly
because the types of mosquito that transmit the disease were thought not
to be sufficiently numerous to sustain transmission to humans. Swallows,
warblers and whitethroats all travel to parts of Africa where the disease
is endemic.
-
- The virus was first identified in women with fever in
the West Nile district of Uganda in 1937 and was first linked to inflammation
of the brain and spinal cord in Israel in 1957. It has spread through many
parts of the world, with outbreaks in humans and horses in parts of Europe
since the 1960s.
-
-
- Guardian Unlimited © Guardian Newspapers Limited
2002
- http://www.guardian.co.uk/medicine/story/0,11381,820628,00.html
|
