Venomous bites and stings are injected poisons. Many
of Tunisia's creatures are particularly poisonous. As for general poisoning, prevention is
better than cure, so take care, when in an area frequented by snakes , scorpions and
spiders, and treat venomous sea creatures with respect.
Scorpions
In
Tunisia:
1)
Introduction
-
40 miles persons aggravated by scorpions in a year in all the regions and especially
in the centre and in the South .Ces scorpioniques poisonings are the causes of several
décés.
-
20 % of the aggravated persons are children between 6 and 15 years ; 8000 pupils a year)
-
It 's impossible to terminate this épedemie ; the only means is the prevention by
the sensation of the pupils and them to let know the techniques of prevention.
2)
Princpaux especes of scorpins:
-
Androctonus australis
-
Buthus occitanus
-
Androctonus aneas
-
Scorpios maurus
3)
Preventions
-
To encourage elevage of the pets: cats, hens , ducks ....
-
Sweeping continues of the yard of the house and its circumference.
-
Avoid accumulating stones or the others at the house
-
Being painted continues walls not to leave cracks in walls
-
Surround the house by a belt of faeince for eviter the penetration of the scorpions at the
house.
-
Avoid sleeping on the ground
-
Set precautions during the harvests or any works of cultures
-
Take premisses in deplacements during the night
-
Verifier before of penetrer hands or feet.
-
Avoid playing in the isolated circles or the circles full of stones or other.
4)
Seours in case of poisoning scorpionique
-
Calm the victim for minimize excitement
-
Avoid the movements
-
Cool the zone of piqure (bags of ice(mirror)) to decrease the pain and slow down the
traffic
-
Transport as fast as possible towards a clinic
-
Reassure
How
dangerous are they?
How many
can kill humans?
There are
about 1400 scorpion species described but there are only about 25 species whose venom is
capable of causing human death, in some cases within several hours (Polis, 1990).
Some of the scorpions might be armed with a highly toxic poison, however, their
sting can be too small that it can hit through our skin.
Where do
they poisonous ones occure?
Most of
the seriously toxic scorpions occure in North Africa, Central America and South America.
They belong almost exclusively to the family Buthidae.
Are the
European scorpions highly toxic?
Members of
the family Chactidae (Euscorpius , Belisarius) are not dangerous for us. The
sting was compared with a sting of a wasp or a bee. However, people with alergeic
reactions to insect toxins should avoid any sting of a 'harmless' species.
Buthus
occitanus and Mesobuthus
gibbosus (Buthidae) were described as potentially dangerous scorpions from Europe.
How do the
dangerous ones look like?
There is
no general rule how you can recognize a potentially dangerous scorpion. However, there are
some characteristics like a very thin and slender pedipalp or a very powerful metasoma
(tail).
This description fits for the members of the family Buthidae which includes
about 500 scorpion species, however, many Buthids are not dangerous for us.
Fig 1: This
scorpion species shows the very slender pedipalps (Chela)
and a very
strong metasoma (tail).
What are
toxins?
Venoms
from scorpions are complex mixtures because they are apocrine secretions. The venom of a
single species contains multiple low-molecular-weight basic proteins (the neurotoxins).
The toxins are single-chain proteins containing 60 to 70 amino acids. Most scorpions have
neurotoxins, however, there are exceptions like Hemiscorpius lepturuswhich has a
cytotoxin
Table 1:
Toxities in mice of venom from various scorpion species.
| Species |
Dose* |
| SCORPIONS
OF MEDICAL IMPORTANCE |
|
| Androctonus amoreuxi |
0.75 |
| A. australis |
0.32 |
| A. crassicauda |
0.40 |
| A. mauretanicus |
0.31 |
| Buthus occitnanus tunetanus |
0.90 |
| Centruroides exilicauda |
1.12 |
| C. limpidus tecomanas |
0.69 |
| C. santa maria |
0.39 |
| Leiurus quinquestratus |
0.25 |
| Parabuthus transvaalensis |
4.25 |
| Tityus serrulatus |
0.43 |
| SCORPIONS
NOT OF MEDICAL IMPORTANCE |
|
| Hadogenes
sp. |
2'000-2'667 |
| Hadrurus
arizonensis |
168 |
| Pandinus
exitialis |
40 |
There
are 8 species around the Mediterranean Sea:
|
Family |
Species |
Description |
Chactidae
Laurie, 1896 |
Euscorpius germanus
(C. L. Koch) |
This
species is alpine and occurs in Northern Italy, Switzerland (Ticino & Grison),
Austria, Crotia, Bosnia and Bulgaria. It is the smallest species of the Euscorpiusgroup
and can be found from 500-2200 m altitude. The highest report of E. germanus is Alp
Terza (Val Müstair, 2200 m) (Braunwalder, 1997).
|
Euscorpius carpathicus
(L.) |
This
widespread species includes 26 subspecies from the mainland, the shores and islands of the
Mediterranean (Hadzi, 1931; di Caporiacco, 1950; Valle, 1975). |
Euscorpius flavicaudis
(Geer) |
This
species occurs in the South of France and in Northern Italy. It occurs from 0-500 m
altitude.
|
Euscorpius
italicus
(Herbst) |
This
species is often associated with relatively dry stone walls of houses where it inhabits
crevices. E. italicus is found in Italy and Switzerland (Ticino, Valais). This
thermophilic species is endangered in Switzerland because of the reduction of dry habitats
due to succesion and due to the disappearing of natural stone walls.
|
Belisarius xambeui
(Simon) |
B.
xambeui is
endemic in the southeastern Pyrenees in France. This is a troglophilic species. |
Buthidae
Simon, 1879 |
Buthus occitanus
(Amoreux, 1789) |
This
species is found in the following regions: Northern Africa, South of Spain, South of
France, Turkey, Greece and on several Islands in the Mediterranean Sea.
|
Mesobuthus
gibbosus
(Brullé, 1832) |
This
species occurs in the 'open very isolated' field (Kinzelbach, 1975). The animals stay
under stones in short selfmade burrows during the day. During the summer they retreat in
relatively large depths in crevices during the day. If there is a phase of aestivation
during the summertime is unknown. The species is found from 0-1600 m
altitude.
|
Iuridae
Thorell, 1876
|
Iurus
dufoureius
(Brullé, 1832) |
This
is the largest scorpion species of Europe (length:males: 98 mm; females: 102 mm). Its
ecologic preferences can be considered as hygrophilic (Kinzelbach, 1975). |
SNAKES
Tunisia's
venomous snakes are regarded as dangerous because of
the frequency with which they come in
contact with humans. Generally, the genus with the most feared reputation is the variety
of Brown Snakes.
These snakes, Tiger Snakes, and the Taipan are responsible for most of the fatal
encounters with humans.
Black Snakes and Death Adders are also dangerous and are known to have caused deaths.
Anti-venom is
generally available for all species.
In most cases, the snake strikes swiftly and injects venom below the surface of the skin
into the tissues. It is then absorbed
by the lymphatic system. Only rarely does the venom penetrate directly into the blood
stream. As the venom is contained
within the lymphatic system, the `John Wayne Method' of slashing the wound and sucking
vigorously, is of no value.
Should you see a snake, LEAVE IT ALONE - do not attempt to kill it as all snakes are
protected by law, and besides, the
creature will defend itself vigorously. Stay clear of likely habitats, and always pay
special attention to young children playing
near long grass and bush. Only approximately 15% of people struck by poisonous snakes are
envenomated, but always treat
for the worst case, and assume that venom has been injected.
SIGNS AND SYMPTOMS
puncture marks, or parallel scratches on the skin - rarely any pain
anxiety
pale, cool skin with progressive onset of sweating
rapid, weak pulse
rapid, shallow breathing
breathing difficulties
blurred vision, drooping eyelids
difficulty swallowing and speaking
abdominal pain
nausea and/or vomiting
headache
collapse - progressing to a comatose state
CARE AND TREATMENT
Make a balance
complete rest
call ambulance urgently
apply direct pressure over the bitten area
obtain a history
apply a firm bandage (pressure immobilisation bandage) starting from just above the
fingers or toes, and wind as
far up the limb as the armpit or groin
immobilise the limb with a splint
send any evidence of the snake to the hospital only if safe to do so.
avoid washing the bitten area, as a venom sample may be obtained
DO NOT use an arterial tourniquet
DO NOT remove the bandage and splint once it has been applied
DO NOT try to capture the snake
SPIDER BITE
FUNNEL WEB SPIDER
The Sydney Funnel Web spider is considered to be the most venomous spider in the world. It
is found in
the NSW coastal zone from Nelson's Bay to Nowra. Its habitat is under rocks and houses, in
a web-lined
burrow. The spider is very aggressive and will attack at the slightest provocation.
Despite its fearsome
reputation, there are only 13 recorded deaths due to funnel web spider bite. However, when
the spider does
inject a dangerous quantity of venom, the effects can be rapid and severe, and death
within an hour may
occur.
A second type of spider called the Bush (or Blue Mountains) Funnel Web is also recorded as
being responsible for fatal
bites. Its habitat ranges over most of the NSW coast and the Great Dividing Range. This
creature lives in trees behind the
bark, or in holes in the trunk. Other types of related spiders such as the Northern and
Southern Tree Dwelling species, are
suspected of similar venom potency, and are found mostly along the south eastern area of
Australia.
There are at least 35 species of funnel web spiders. All are medium to large, robust
spiders, mostly dark or black in colour,
with stout legs and large fangs. Males search for female mates, a process which may
increase the chance of unwanted
interaction with people, as they may get underfoot, or into shoes or clothing left on or
near the floor.
The Funnel Web will bite successively if in contact with the skin, and when bitten by the
Funnel Web Spider the venom
enters the body similarly to that of snakes. Anti-venom is available.
SIGNS AND SYMPTOMS
vomiting
abdominal pain
copious production of saliva and pulmonary fluids
mental confusion
collapse - coma - death
CARE AND TREATMENT
as for snakebite
RED-BACK SPIDER
This spider with the telltale red or orange mark on its thorax is the female of the
species. It is common all
over Australia, and its preferred habitat is under any old building material, or inside
sheds and garages. The
spider's bite is not generally regarded as fatal, although there are recorded deaths,
including a five year old
boy who died in 1952 from a red-back's bite. Less than 20% of bites actually result in
significant
envenomation, but generally, the bite is very painful, and causes distress.
SIGNS AND SYMPTOMS
intense pain at the site of the bite
may be localised redness, swelling and sweating
nausea, vomiting and abdominal pain
rapid pulse
rapid, shallow breathing
CARE AND TREATMENT
Make a balance
obtain history
cold compress to relieve pain
observe casualty for any sign of deterioration
OTHER SPIDERS
Other spiders that have been associated with venomous bites are the White-Tailed Spider,
Trapdoor Spider and Wolf
Spider. The bite of these spiders causes tissue necrosis, the death of the tissue around
the bitten area. A doctor should treat
bites from these spiders and assess the bitten area over a period to observe for any
detrimental effects.
White-tailed
spider
Trapdoor spider
Wolf spider
TICK BITE
Only the Australian paralysis tick or `scrub tick' causes envenomation in humans. Ticks
are capable of
spreading diseases eg. scrub typhus. Ticks can be found anywhere on the body, but hairy
areas, skin clefts
and crevices should be examined carefully.
SIGNS AND SYMPTOMS
local irritation
lethargy
muscle weakness, especially children
unsteady gait
double vision
difficulty in swallowing or breathing
rarely allergic reactions occur:
rapid local swelling
wheezing and difficulty breathing
collapse
Symptoms and signs generally develop over several days but allergic symptoms can occur
within hours.
CARE AND TREATMENT
Make a balance
find and remove the tick by spraying with tick killing repellent, preferable containing
pyrethrins or pyrethroids. If
not available, kerosene can be used
if the victim has a history or signs of allergy:
- use pressure immobilisation if possible
- seek medical advice immediately
if tick repellent not available - slide the open blades of sharp pointed tweezers on each
side of the tick and lever
it upwards
always check the whole body of the victim, including the ears, skin creases and hair for
further ticks
after removal of a tick the victim should be advised to see a doctor to check that no
further treatment is required.
avoid squeezing the tick because even slight pressure may inject more venom
BEE AND ANT STINGS
Bee
and ant stings for most people are only a temporary irritation. For others, however, these
stings have the
potential to cause death. The venom associated with bee stings causes a severe allergic
reaction in
susceptible people, and can cause respiratory and cardiac arrest. In most cases ant
stings, while painful,
rarely cause serious problems.
SIGNS AND SYMPTOMS
evidence of bee sting with the barb present
pain and itching at the site
swelling of the stung area
in allergic casualties;
onset of wheezing and breathing difficulties
facial swelling and hives
rapid pulse
collapse
CARE AND TREATMENT
Make a balance
remove bee sting by scraping with fingernail or similar
cold compress to reduce swelling and pain
if onset of allergic reaction;
pressure immobilisation bandage
call 000 for an ambulance
avoid squeezing or touching the barb
EUROPEAN WASP
This introduced insect has been identified with at least one death. The European Wasp is
coloured yellow
and black, with stripes similar to those of a bee. The yellow stripes are brighter in
colour than those on a
bee, and the insect is slightly larger. The insect is attracted to aromatic or
sweet-tasting things, and will
enter food containers such as open soft-drink cans. The creature will then sting when
inadvertently handled.
Similar to bees, the wasps become aggressive when their nest is disturbed.
SIGNS AND SYMPTOMS
severe pain at the affected site
immediate swelling, especially if the throat has been stung
breathing difficulties
CARE AND TREATMENT
*Make a balance
*call an ambulance or see own doctor
*cold compress to reduce swelling and pain
*if onset of allergic reaction;
*pressure immobilisation bandage over affected limb(s)
*call ambulance urgently
*EAR if respiratory arrest
SEA CREATURES
Many sea creatures are venomous, and the best way to avoid envenomation is
to give the creatures a wide berth. As an
example, don't pick up or handle creatures washed up on the beach or in rock pools, and
don't swim where Box Jellyfish or
Portuguese Man-'0-War are prevalent.
BOX JELLYFISH
The Box Jellyfish, also known as `Sea Wasp' and `Stingers', are prevalent in the north of
Australia during the season from
November to March. These creatures are deadly, and are responsible for many fatal
encounters. Warning signs at popular
beaches should be complied with, and extreme care taken at unpatrolled locations.
SIGNS AND SYMPTOMS
immediate severe pain, with irrational behaviour because of the pain
rapid, irregular pulse
frosted pattern of sting marks
collapse
respiratory arrest
cardiac arrest
CARE AND TREATMENT
Make a balance
restrain anyone from rubbing the sting for around 30 seconds
apply liberal quantities of VINEGAR
for major stings only, apply immediate pressure immobilisation bandage to areas treated by
vinegar
cold compress to relieve pain
call an ambulance or call lifesavers urgently - they have antivenom available
EAR and/or CPR as required
STONEFISH
The Stonefish is virtually invisible amongst rocks. The creature has venomous spines on
its back that it erects when
threatened or stepped on. This fish lives in the tropical regions, and as far south as
Forster/Tuncurry in NSW.
SIGNS AND SYMPTOMS
severe pain at the site of envenomation
swelling
open wound and/or bleeding
irrational behaviour
rapid pulse
breathing difficulties
collapse - coma
CARE AND TREATMENT
Make a balance
call an ambulance
HOT water immersion of the site to relieve pain - ensure that the water will not scald the
casualty
EAR and/or CPR as required
BLUE-RINGED OCTOPUS AND CONE SHELL
The Blue-ringed Octopus is an attractive little creature that lives in rockpools on the
shores of Australia. When threatened,
the creature `pulses' luminous bright blue rings on its body. Its bite is painless, and
will only occur if the creature is handled.
The Cone Shell is a variegated shell, usually brown and white, which is common on tropical
beaches. The shell contains a
dagger-like spine, which can inject toxin into any unwary person who handles the creature.
SIGNS AND SYMPTOMS
a spot of blood
numb feeling of the face and tongue
progressive weakness in the legs and body
eventual collapse
respiratory arrest
CARE AND TREATMENT
Make a balance
reassurance
pressure immobilisation bandage
call ambulance urgently
EAR as required
PORTUGUESE MAN-'O-WAR (`BLUEBOTTLE')
The Portuguese Man-'O-War, or `Bluebottle', found on most beaches in Australia, is really
a colony of small creatures living
as one. The creatures have small stinging cells, which when encountered as a group, impart
a venomous sting. People who
are susceptible to bee sting are usually sensitive to Bluebottle venom.
SIGNS AND SYMPTOMS
'trails' of blue `tentacles' adhering to the body or limbs
stinging sensation associated with the contact
reddening of the skin
pain for some hours
may cause severe allergic reaction (rare)
CARE AND TREATMENT
Make a balance
remove the `tentacles' with a copious amount of sea water
dry cold compress to relieve pain
call ambulance or own doctor
if severe allergic reaction:
pressure immobilisation bandage
call 000 for an ambulance
FISH STINGS
Many fish, such as the flathead and the stingray, have poisonous spines that can inject
venom deep in the unwary victim,
causing excruciating pain. Handle all fish with care, avoiding the spinous areas along the
backbone and around the gills.
SIGNS AND SYMPTOMS
intense pain at the site
swelling
bleeding
often a grey/bluish discolouration at the site
there may be an open wound or barb in the skin
irrational behaviour or panic may occur
CARE AND TREATMENT
Make a balance
HOT water immersion of the site to relieve pain or apply a hot compress - ensure that the
water will not scald the
casualty
if heat does not alleviate the pain, try a cold compress for pain relief
call an ambulance or call own doctor
Also be aware that constant handling of fish may cause skin irritation due to the fluids
and secretions of the fish oils.
If handling fish without protective gloves, wash hands frequently to avoid skin problems.