By Gorm PalmgrenTwo million people are poisoned by snake bites annually, and 130,000 of
them die. The treatment has been the same for 100+ years, but now scientists
are ready to combat the venom with an arsenal of antibodies and nanoparticles.Scientists’ new weapon to
save millions of snake victims
Two elephants in one bite
Europe and North America don’t have any very poisonous
snakes, but these are very common in the rest of the
world, particularly in India, South-East Asia, and of course
Australia. However, the most poisonous snakes are not
necessarily the most dangerous ones, and the hazard
level of snakes is generally difficult for scientists to rank.
Technically the inland taipan, which lives in dry areas of
Australia, is one of the world’s most poisonous snakes.
A particular neurotoxin known as taipoxin makes the
snake’s venom cocktail so powerful that one single bite
could kill two African elephants or 100 people. However,
other snakes such as the South American Bothrops asper
are much more aggressive to humans, and the Indian
spectacled cobra is particularly dangerous because it
seeks out villages and other inhabited areas.T
he East African farmer doesn’t
hear the faint rustle on the
ground as he walks through his
corn-field. A light grey snake
rises slowly from the side, and
when the small head hovers beside the
farmer’s hip, it opens its mouth wide and
utters an ominous hiss. From the top of its
ink-black mouth two backward-facing fangs
quickly enter the farmer’s forearm, leaving
several drops of lethal neurotoxin.
At first, the farmer feels the venom only
as a weak, tingling sensation. But after 10
minutes, the initial weak tinglings expand
into involuntary muscle contractions, with
sensory disturbances spreading through his
arms and face. After 40 minutes, the farmer
can no longer walk. After 45 minutes,
muscular paralysis is making it difficult for
him to breathe.
Throughout the world, some 2.3 million
people are severely poisoned by snake bites
annually. Of these 130,000 die, and another400,000 become permanently disabled. The
treatment of the victims is a huge challenge.
Anti-venom is expensive to make, and often
causes severe side effects. Given the rural
scenarios likely for many snake bites, it can
also be difficult to make sure that the right
antivenom is available to small hospitals in
potentially sparsely-populated areas. But
now, scientists from the University of Costa
Rica and the Technical University of
Denmark have completed the development
of new types of antivenom and DNA analysis
techniques which may be able transform
treatment of potentially deadly snake bites.Goal to reduce deaths by 50%
Most snake-bite victims in the world are
farmers, attacked as they attend to their
crops or handle their domestic animals. The
situation is particularly severe in India,
Africa, and Southeast Asia where the most
poisonous snakes live – more than our fair
share of them, of course, here in Australia.According to the WHO, snake bites are a
disease of poverty, the victims either not
hospitalised in time or unable to afford the
necessary treatment. This can be seen by
comparing data from two islands — our own
prosperous Australia, and the neighbouring
island of New Guinea, where one in three
people are poor. In both Australia and New
Guinea there are about 100 different
venomous snakes, but in Australia the
snakes cause two deaths a year, compared
to more than 1000 annual deaths as a
consequence of snake bite in New Guinea.
Generally, venomous snakes are a
relatively disregarded threat to health,
despite claiming more victims than any
known tropical disease, such as dengue
fever. In 2018, the numbers made the WHO
sound the alarm and introduce a plan which
aims to reduce deaths and disability victims
by 50% before 2030, and scientists are
working hard on projects which could help
give a fillip to those fine intentions.KING
COBRABLACK MAMBA BELCHSEA SNER'SAKEVIPERBOTHROPS ASPER INTAIPANLANDTIGER SPECTACLED COBRA
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