Paul Brown The Guardian
Why do
we need to slaughter infected animals?
The first reason is to stop the disease spreading, the second
is economic. The virus is virulent and would spread through the
entire population of cloven-hoof animals. Although nearly 50,000
animals, mostly sheep, have already been killed in this outbreak
to prevent an epidemic, millions more would eventually be infected.
There are 40m sheep and 10m cattle in Britain, plus domestic and
wild pigs, deer and goats. Normally live animals are exported
for breeding, and thousands of sheep for slaughter, but all this
trade has been stopped and could never resume to countries free
of foot and mouth if we did not eradicate this disease.
What effect
does foot and mouth have on animals?
Although most
animals do recover, about 5% of young and older animals die. Animals
get sore mouths and feet, and stop eating as much, and so do not
gain weight; cows' milk yield goes down. Animals go lame and in
some cases get severe foot infections which would lead to slaughter
to prevent suffering. These losses could make farms uneconomic.
How long
would it last if allowed to run its course?
Each outbreak
would last only a few weeks in each farm before the animals appeared
well. Vaccination of other herds and flocks which had not had
the disease would protect them against infection and illness.
Millions of shots of vaccine are in stock. The problem is that
this accepts the disease is here to stay. Foot and mouth in the
national herd bars animal exports to "clean" countries
because of fear of infection. Slaughter is a controversial policy
but kept the UK foot and mouth-free for 20 years. It remains British
and EU policy, although it could be reviewed once the outbreak
is over, or if the disease keeps recurring in Europe. Greece has
had outbreaks twice in five years.
What happened
in the last outbreaks?
In 1967 400,000
animals were slaughtered and the disease took six months to get
under control. In 1981 there was one outbreak in the Isle of Wight.
Why has
it arrived after 20 years?
There is a
worldwide epidemic of a virulent virus of foot and mouth called
Type O which reached 60 countries in 1999. South America, South
Africa and Asia have all had outbreaks. The immense increase in
free trade - making import restrictions more difficult - means
infected meat is traded round the world. That makes more countries
vulnerable to outbreaks. Once present it spreads very quickly
and can travel more than 100 miles as an airborne infection.
Can humans
catch the disease from animals?
Yes, but very
rarely and only thought to be by direct handling of sick animals.
There were cases in the 1960s epidemic and children under 10 are
most likely to suffer. In humans it is like flu but with an added
sore mouth. People must be kept in quarantine until they have
recovered.
Would the
meat of animals with foot and mouth be infected?
Yes. This
is the most likely way the infection came to Britain in the first
case. Imports of meat from countries with foot and mouth are banned
but infected meat fed to pigs in Northumberland in swill is regarded
as the most likely cause of the outbreak, although the cause is
still under investigation. Food containing the virus brought in
from another country and carelessly thrown away in Britain is
another possible cause. Countries must be disease-free for six
months before exports are allowed. For infected meat to have reached
Britain some illegal practice must have occurred.
What would
the effect on humans be from eating infected meat?
None. Properly
cooked meat kills the virus and it would not be in sufficient
quantities to get past the human defence system. Animals are far
more susceptible.
What about
wild animals?
These are
far less likely than farm animals to catch foot and mouth because
they have less contact with infected animals. The rapid spread
of infection so far has been caused by the mixing of sheep in
markets and transporting them long distances crowded in lorries.
If wild boar did get foot and mouth they would be the most likely
wild animal to spread the disease because, like domestic pigs,
they "shed" large quantities of virus . But experts
think infection of wild animals is unlikely. Culling poses difficulties
because frightened animals are likely to disperse, spreading the
infection further than leaving them alone would do.
What's going
on?
Outbreaks
and precautionary measures
Interactive
guide: tracing the epidemic
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