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most deadly venomous snakes in the world: cobras, kraits,
taipans and sea snakes. Like all elapids, coral snakes produce
a potent, neurotoxic venom that is very different from the
primarily hemotoxic, cytotoxic and myotoxic venom of
the pit vipers. North American coral snakes are generally
smaller than pit vipers (typically about 2 feet long) and have
a distinctive red, yellow and black banded pattern. This
pattern closely resembles that of several other nonpoisonous
snakes, but there is a key difference. The rhyme, “Red on
yellow, kill a fellow; red on black, venom lack” is reliable, at
least in North America, for distinguishing coral snakes from
nonpoisonous species. If the red bands touch the yellow
bands, stay away. Despite the toxicity of the coral snake’s
venom, the incidence of injury is very small. The snakes are
timid and prefer to stay out of sight, underneath rotting logs
or stones, for example.
In North America snakebites occur primarily because
people accidentally step on snakes or intentionally provoke
them. Alcohol intoxication is commonly associated with
snakebite, particularly bites in which the person was
attempting to capture, kill or antagonize the snake. If
someone has been bitten by a snake, no matter whether
there are symptoms or not, wash the wound with soap
and water. Stay clear of the snake, and do not attempt to
capture it. Keep the victim calm and still. Victims should be
evaluated by a doctor as soon as possible, but they should
not walk or exert themselves if it can be avoided. Venom
can cause swelling, pain, weakness, numbness, nausea and
vomiting, but it is worth noting that approximately one
quarter of bites by venomous species are dry, which means
no venom is delivered. Prepare for swelling by removing
watches, rings or other jewelry. Splint the extremity
to minimize movement. Although many different folk
remedies have been recommended for treating snakebites,
most are not helpful, and many are dangerous. Never
cut, suck or apply ice, heat or electricity. Coral snake
bites warrant the same treatment, with the addition of a
pressure immobilization bandage on the entirety of the
affected limb. A wide elastic bandage (such as an ACE wrap)
should be applied, starting at the extremity and wrapping
toward the core. Coral snakes’ neurotoxic venom can cause
respiratory failure in a matter of hours, so artificial or
mechanical ventilation may be required to save a person’s
life. Antivenom, if available, may also be an important
component of snakebite emergency care.
ArAchnids
In North America severe scorpion envenomations come
from a single genus, Centruroides, commonly known as
the bark scorpions. Bark scorpions are actually among
the smaller scorpions to be found in the North America,
but their venom is much more potent than that of the
continent’s other scorpions. Stings are immediately painful
and can cause redness, swelling, numbness and tingling.
Nausea, vomiting and incontinence are also possible.
Of the spiders that inhabit North America, two stand out
as the most dangerous. Widow spiders, so named due to a
penchant among some females of the genus to eat the male
after mating, are one of them. Widow spiders, including
the common black widow, can be found in moist, dark
places such as the crawl spaces of homes. Widow spiders
sometimes have a red hourglass symbol on them, but it may
appear as two red dots. Recluse spiders are infamous for their
dermonecrotic bites that cause serious skin lesions. The fear
these spiders induce leads to them being blamed unfairly
for a number of ugly skin problems. Various wounds, burns,
infections and diseases are often mistaken for brown recluse
bites. One expert estimated that 80 percent of suspected
brown recluse bites are actually misdiagnoses.
Bites and stings by North American spiders and scorpions
are rarely serious, typically no more severe than bee stings.
Clean wounds with soap and water, then apply ice or cool
water. Closely monitor anyone who has been bitten by a spider
or stung by a scorpion, and seek immediate medical attention
if serious symptoms occur. These may include blurred vision,
difficulty swallowing and cardiovascular or respiratory distress.
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