The venom is a substance Toxique which is a complex mixture of varied chemical substances, especially of the Enzyme S which was used at the origin to facilitate the Digestion Proie S. Plus these gastric juices are concentrated, plus venom is powerful.

Animal venom versus vegetable toxin

The term of venom is reserved for toxins secreted by the animals. In the case of poisonous plants, one prefers not to speak about venom but rather to speak about toxins or poisons.

Components of venom

The main components of venom are enzymes like the Protéase S, which destroys the fabrics, the Hyaluronidase, which increases the permeability of the fabrics (venom can be propagated more quickly), the Phospholipase S, which attacks the cellular membranes, and the Phosphatase S, which degrade various chemical compounds.

Venom is a compound of Polypeptide S assembled in chains alpha and beta. Each peptide is responsible for a character of venom. The characters of venom the most accused in death by inoculation of venom are the neurotoxines , which directly assign the Exocytose to the level of the Neuron S, which generates a paralysis of the muscles and disorders respiratory.

Other peptides are responsible for the denaturation of the cells of the Pancréas for example, these peptides destroy the small islands of Langerhans which, not being able more to secrete insulin nor of gastric juices involve Hyperglycémie S causing of the Impaired renal function S, Impuissance, Myocardial infarction, Gangrène,… It is the combination of these peptides assembled in chains which make ic venom scorpion, a mortal mixture: one dies of the continuations of the consequences of this puncture.

Types or categories of venoms

In the past one determined the types of venoms according to two types of symptoms: action either on the blood System, or on the Nervous system (neurotoxic). In practice, this distinction is not so simple. Thus a venom which disturbs the blood system often causes nervous disorders and conversely. And a venom can be at the same time anticoagulant and Coagulant, which complicates the treatment then.

The principal toxic agents of venoms are the following:

• of the paralyzing neurotoxines whose action is comparable with that of the Curare (“curare-like”) but which is not thwarted by the antagonists of curare the such ésérine (this product will be thus useless in the case of survival);

• of the hémorragines , very marked at the vipéridés , causing Hemorrhage S;
• of the cytolysines destroying the cells at the origin of Necroses S sometimes cutaneous very important, going to the bone (Myotoxine of hydrophidés in particular);
• of the hemolysins more specifically attacking the red globules of blood (see Hémolyse), preventing the Phagocytosis in particular, explaining the frequent secondary infections;
• of the histaminic substances involving reactions Vasomotrice S persons in charge of the shock observed after bite by the vipéridés . There exists much of other substances to the very diverse enzymatic actions.

And as all venoms combine several of these actions, that makes then a systematization of venoms impossible.

List effects and actions of venoms on the organization

• neurotoxic Effects on the nervous system, the brain and the spinal-cord,

• Paralysis of the respiratory system.
• Action coagulating on blood,
• Deterioration of the blood-vessels causing of the hemorrhages,
• anticoagulant Action,
• Destruction of the red globules,
• Action on the heart, lowers blood-pressure,
• intense Salivation being able to cause a smothering,
• Altération of the cells, fabrics and even of bodies (kidneys, etc),
• Œdème S (cause a smothering if the bite is made on the face or the neck),
• Nécroses.

Venoms of the snakes

That of many the Colubridae contains also an L-acid-amino-oxydase, substance which destroys fabrics. The venom of the snakes of the family of the terrestrial and marine Elapidae contains basic Polypeptide S, which block the nervous transmission and cause a fast death by paralysis of the diaphragm, so that the victim stops breathing. The venom of the Viperidae, contains an high rate of Protéase S, which produces severe damage with fabrics surrounding the point of bite. It leads to a abundant Hémorragie.

Poisonous animals

The Venin is secreted by a special gland which certain animals like the Cœlentéré S have (Sea anemone, Méduse S, Hydre S…), some Gastropodous (cone…), the Spider S (Arachnida), the Myriapode S (millepede), various Insect S (of which many Hyménoptère S), certain fish (the Lives, the Rascasse, the Poisson hones…), some Serpent S, some Lézard S (the Héloderme S of the Western American), the scorpions, some Batracien S (like the Dendrobate S and the Crapaud Bufo alvarius) and even of the mammals Monotrème S (the Ornithorynque and the echidna S), and insectivorous (the Blarine with short tail of North America and the Solénodons of the Antilles, this last in process of extinction). These animals are known as poisonous . They use to them Venin to push back, kill or wound their preys, their enemies, their predatory or their competitors. Venom can be injected by puncture or bite, even with simple the Toucher, as at the Grenouille S Dendrobate S. has not to confuse with the animals Vénéneux whose ingestion is toxic (for example the Fugu, the Diodon, the Poisson-coffre, etc…).

The Australia is the only country where one finds more snakes poisonous than nonpoisonous. It is also the country where one finds the greatest number of poisonous animals in the world. These last animals are also among the most poisonous species in the world.

With the Venezuela, there exists between 150 and 200 species of scorpions, inoffensive for the human being, but those pertaining to the kind Tytius (containing 28 species) are very dangerous. Any puncture of scorpion taking place with more than 600 meters above it sea level must be regarded as dangerous.

One classifies sometimes the Dragon of Komodo - a giant monitor of Indonesia and the largest current lizard -, like poisonous , because its saliva, container of the pathogenic bacteria, is toxic.

Treatments

It is not easy to determine if a bite of a species of snake presents or not a vital danger. A bite by a viper coppered on ankle causes usually damage moderated for an adult in good health, but the bite of the same snake to the abdomen or the face of a child can be mortal. The results of all the bites of snakes depend on a multitude of factors; size, the physical status, the temperature of the snake, the age and the physical status of the victim, the sector and the fabric bitten (for example, foot, chest, vein or muscle, etc), quantity of venom injected, and finally the time passed between the bite and the moment when the patient is treated médicalement and the quality of the treatment.

Identification of the snake

The identification of the snake is important in the planning of the treatment, but not always possible. In the best of the cases the dead snake should be paid with the patient, but in the sectors where the bite of snake is more common and more local knowledge can be sufficient to identify the snake. In the countries where only the general-purpose antivenins are available, the identification of the snake does not have much importance. The three types of toxic snake which pose the majority of principal clinical problems are the viper, the coral snake and the cobra. The good knowledge of the local species can be crucial, just as the knowledge of the signs and the typical symptoms of envenimement for each one of the species of snake. Systems of evaluation can be employed to test and to determine the snake in question based on the clinical devices but these systems of evaluation are extremely specific to a particular geographical sector.

The keys of determination of the species are invariably the same ones. They refer to the number of scales of the head, the lips, of the temples, with their color, the type of teeth… a little game of tiresome patience, requiring that the snake is quite passive, and thus out of matter in situation of survival. Multicoloured boards representing some of the species considered dangerous have utility only for the pleasure of the eyes, inevitably omitting the greatest number of them. Certain great identifying information will be sufficient.

According to general dimensions

A very long snake, higher than 5 meters, will be regarded as one boïdé (of the family of the boas), nonpoisonous, able nevertheless to bite the made-to-order of a dog or to even choke to kill, if it is annoyed.

A snake of very large diameter (anaconda) will be also regarded as inoffensive on the poisonous level, but there too, it is to better avoid approaching the animal. The Indians of South America know it well, they often walk with a needle of Porc-épic to the reverse of the loincloth, the animal slackening its pressure by reflex as soon as it is piqué. More prosaically, the commandos survival are satisfied with a needle.

A snake even of a size lower than 20 centimetres could be dangerous if it is about a young person of a poisonous species. As of the birth, indeed, venom is present in glands.

The poisonous snake heaviest is the crotalus adamanteus , variety of rattlesnake of the south-east of the the United States, which weighs only 15 kg. An at the same time long and sufficiently large snake to exceed 15 kg is never poisonous.

According to the morphological characters

One will refer to the table of classification (table in construction).

According to delivered

It is false to believe that delivered of a snake allows to distinguish a poisonous species from another. Grass snakes of kind lampropeltis (snake king), inoffensive, resemble there to mistake with Elapidae of kind micrurus (coral snake) which, even if they are equipped with small hooks which make the envenimations human rare, have a frightening venom. Moreover, delivered animal depends enormously on its medium, one will thus meet vipers with delivered very dark, even melanic (black) in altitude and clearer in plain.

According to the scales

For the European species only, one can consider that the larger the number of scales is on the level of the head, the more the risk is tall. Thus, the grass snakes have only nine large scales on the head, unlike the vipers. Attention however, Malpolon Monspesulanus (the grass snake of Montpellier) is a grass snake Opistoglyphe, which wants to say that it has poisonous hooks behind of the mandible able to inoculate venom with small preys. It is advisable to be very careful in the surfaces of distribution of the Elapidae or this rule does not apply any more, Elapidae (family of the Cobra S, coral snakes and Mamba S having them also nine large scales to the head, as well as the Vipéridés of the kind Causus present in Africa. Contrary, the Boidés, nonpoisonous, have multiples small scales on the head.

The shape of the scales is also evocative: scales careened the made-to-order of a hull of boat turned over are synonymous with danger. Thus at Echis carinatus , the viper of the pyramids with which perhaps Cléopâtre committed suicide.

It should be noted that all the poisonous snakes are snakes more advanced than the others. That morphologiquement results in ventral scales systematically as broad as the bearing surface. However certain nonpoisonous snakes such as those of the family of the colubridés have also ventral scales as broad as the bearing surface. On the other hand, all the not very advanced snakes such as the boïdés having scales ventral smaller than the bearing surface of their body will be without any nonpoisonous doubt, which does not want to say inoffensive compared to the size of certain individuals.

According to the mode of progression

The majority of the vipéridés (and the boïdés ) have a rectilinear and nonundulatory progression. Vipers known as " heurtantes" kind alive Cerastes in the desert mediums, move laterally, by taking support only by two drawn aside points, mainly to reduce the surface of contact of their body with the extreme ground.

According to the mode of intimidation (or position of attack)

Certain snakes take a characteristic attitude when they are worried or excited.

The Naja S vertically draw up the former third of their body, curving the head behind almost with right angle, and inflate their neck by spreading out their “cap”.

Certain vipers show as a side dilation, but much more reduced as at the najas. The vipéridés , in general, are coiled, bending their neck in S, while raising on a horizontal level the former part of their body above the ground. The relaxation is then very brutal and fast. At once after being itself projected ahead, the snake opens its mouth and rocks its jawbones, projecting its hooks forwards the, right one before the contact of the prey or the adversary.

Other snakes inflate their neck by inspiring a great quantity of air, which they drive back in the trachea all locking up the glottis ( Dispholidus Typhus ), frightening the Thelotomis Kirtlandi makes in the same way in the vertical direction, the swelling of the neck revealing bright colors, nonapparent at rest. This snake, at the same time, darts its language coloured in vermilion. The Mamba S also swell their neck in the vertical direction.

Certain species emit noises of intimidation: thus the Bitis (family of the viper of Gabon) which blow very bruyamment when they are worried; the viper of Russel emits a whistle when it is irritated. Others ( Echis and cérastes) blow and emit also a characteristic squealing by rubbing one against the other their ducted scales. The Crotale makes resound its caudal appendix named Cascabelle. All these attitudes are the first steps of an imminent attack and they thus should be known, even if the involved species is not recognized.

Treatment

See also: Envenimation

Contrary to the generally accepted ideas, in the event of bite of snake, first aid of the treatment of a envenimation is generally summarized to reassure the victim, while being based on the fact that 50% of the bites are white, therefore without inoculation of venom and that among the frank bites, there remains a great proportion about it where the volume of venom injected is not sufficient to engage a vital prognosis and to take care to keep it motionless, in a position semi-base or lengthened. It then only remains to give alarm and to await the helps. If the bites of Elapidae are mortals in a few hours, the time goes up at more than one day for the majority of vipéridés.

The use of equine serums is better and better tolerated by the victims progressively of the progress made by the pharmaceutical companies in term of purification of the serum. However, one should not manage serum without downstream of a doctor.

Immobilization by pressure (points of compression)

The immobilization by pressure cannot be appropriate to the bites with cytotoxic venoms like those of the majority vipers, but is strongly effective against venoms Neurotoxique S like those of the majority of the Élapidés. Developed by Struan Sutherland in 1978, the object of the immobilization by pressure is to contain venom in the bitten member and to prevent it from moving with the lymphatic system with the essential bodies in the heart of the body. This therapy has two components: pressure to prevent lymphatic drainage and immobilization of the member bitten to prevent the action of pumping of the muscles of the skeletons. The pressure is preferably applied with an elastic binding, but any fabric will make in the event of urgency. The stringcourse start from 5 to 12 cm (two to four inches) above the bite (i.e. between the bite and the heart), being rolled up around, overlapping and advancing towards the heart, to go down then to move back on the bite and in front of it, towards the hand or the foot. The member must be held motionless, held if possible with a splint. Binding must be tight, does not have to cut the flow of blood, or to be even uncomfortable; if it is uncomfortable, the patient will bend the member unconsciously, demolishing the part of the laying-up system. The site of the bite must be clearly marked on the outside of bindings. Some edema S peripherals can be a consequence awaited/envisaged of this process of immobilization.

Apply as quickly the immobilization by pressure as possible; if you await before the symptoms do not become considerable you will miss the best moment to carry out this treatment. Once a binding of pressure was applied, it should not be removed before the patient did not meet a professional of the medical sector. The combination of pressure and the immobilization can contain venom so effectively that no symptom is visible for more than twenty four hours, giving the illusion of a dry bite. But it is only one delay; the removal of binding then diffuses this venom in the system of the patient with a probably fatal speed and consequences.