The snake is a powerful symbol in Indian Mythology and Hinduism. The snake (‘Nag’ as they are commonly called in Hindi language) is worshipped by people across the country. Some of these mythical snakes are considered to be ‘protectors’, while others are thought of as ‘destroyers’.
The picture of Lord Shiva is incomplete without the Cobra around his neck . Another Indian God, Lord Vishnu, rests on a seven headed snake. There are hundreds of references to snakes with mythical powers in Indian stories. These have made the snake a powerful symbol in Indian Culture.
But there are thousands of beliefs and myths surrounding snakes, widespread in the country, which are misleading. Most of these myths are spread by snake charmers for their livelihood.
Snakes are remarkable animals, successful on land, in the sea, in forests, in grasslands, in lakes, and in deserts. Despite their sinister reputation, snakes are almost always more scared of you than you are of them. Most snakes do not act aggressive toward humans without provocation.
Snakes are meat eaters and they catch prey that includes insects, birds, small mammals, and other reptiles, sometimes including other snakes. Only about 400 of 3,000 snake species worldwide are venomous. About 25 species of venomous snakes are found in North America.
Many snakes kill their prey by constriction. In constriction, a snake suffocates its prey by tightening its hold around the chest, preventing breathing or causing direct cardiac arrest. Snakes do not kill by crushing prey. Some snakes grab prey with their teeth and then swallow it whole.
Poisonous snakes inject venom using modified salivary glands.
During envenomation (the bite that injects venom or poison), the venom passes from the venom gland through a duct into the snake’s fangs, and finally into its prey.
Not all bites lead to envenomation. Snakes can regulate whether to release venom and how much to release. “Dry Bites” (a bite where no venom is injected) occur in between 25%-50% of snake bites.This variation is species specific with approximately 25% of pit-viper bites being “dry” and up to 50% of coral snake bites. Snake venom is a combination of numerous substances with varying effects.In simple terms, these proteins can be divided into 4 categories:
Cytotoxins cause local tissue damage.
Hemotoxins cause internal bleeding.
Neurotoxins affect the nervous system.
Cardiotoxins act directly on the heart.
The number of bites and fatalities varies markedly by geographic region. Reporting of snakebites is not mandatory in many areas of the world, making it difficult to determine the number of bites.
Snakebites are more common in tropical regions and in areas that are primarily agricultural. In these areas, large numbers of people coexist with numerous snakes.
People provoke bites by handling or even attacking snakes in a significant number of cases.
Venomous Snakes Most Dangerous to Humans
Two major families of snakes account for most venomous snakes dangerous to humans.
1. The elapid family includes:
The cobras (Naja and other genera) of Asia and Africa;
The mambas (Dendroaspis) of Africa;
The kraits (Bungarus) of Asia;
The coral snakes (Micrurus) of the Americas; and the Australian elapids, which include the coastal taipan (Oxyuranus scutellatus),
Tiger snakes (Notechis), king brown snake (Pseudechis australis), and
Death adders (Acanthophis).Highly venomous sea snakes are closely related to the Australian elapids.
Snakes from the elapid family
King cobra (Ophiophagus hannah), a dangerous Asian elapid and longest of the venomous snakes at around 4 m (13 ft).
Black mamba (Dendraspis polylepis), an extremely fast, large, and dangerous African elapid.
Coral snake (Micrurus fulvius), a shy American elapid that accounts for only about 1% of venomous snakebites in the United States. Recognize it by this catch phrase: “Red on yellow, kill a fellow.”
Milk snake (Lampropeltis triangulum), a harmless mimic of the coral snake. “Red on black, venom lack,” although this old saying becomes unreliable south of the United States.
2. The viper family includes:
The rattlesnakes (Crotalus) (Western diamondback rattlesnake and timber rattlesnake),
Moccasins (Agkistrodon), and
Lance -headed vipers (Bothrops) of the Americas;
The saw-scaled vipers (Echis) of Asia and Africa;
The Russell’s viper (Daboia russellii) of Asia; and
The puff adder (Bitis arietans) and Gaboon viper (Bitis gabonica) of Africa.
Snakes from the viper family
Western diamondback rattlesnake (Crotalus atrox), an American pit viper, with rattle vibrating. This is one of the most dangerous snakes of North America.
Timber rattlesnake (Crotalus horridus), American pit viper, caught yawning after a big meal.
Cottonmouth or water moccasin(Agkistrodon piscivorous), American pit viper usually found in or near water.
Northern copperhead (Agkistrodon contortrix), an American pit viper. Bites by this species tend to be less severe than rattlesnake or water moccasin bites but still require urgent medical attention.
Most species of the most widely distributed and diverse snake family, the Colubrids, lack venom that is dangerous to humans. Some species, however, including the boomslang (Dispholidus typus), twig snakes (Thelotornis), the Japanese garter snake (Rhabdophis tigrinus), and brown tree snake (Boiga irregularis), can be dangerous. Other members of this family, including American garter snakes, kingsnakes, rat snakes, and racers, are harmless to humans.
Bites by venomous snakes result in a wide range of effects. They range from simple puncture wounds to life-threatening illness and death. The findings following a venomous snakebite can be misleading. A victim can have no initial significant symptoms, and then suddenly develop breathing difficulty and go into shock.
Signs and symptoms of snakebites can be broken into a few major categories:
Local effects: These are the effects on the local skin and tissue surrounding the bite area. Bites by vipers and some cobras (Naja and other genera) are painful and tender. They can be severely swollen and can bleed and blister. Some cobra venoms can also kill the tissue around the site of the bite.
Bleeding: Bites by vipers and some Australian elapids can cause changes in the victim’s hematologic system causing bleeding. this bleeding can be localized or diffuse. Internal organs can be involved. A victim may bleed from the bite site or bleed spontaneously from the mouth or old wounds. Unchecked bleeding can cause shock or even death.
Nervous system effects: The effect on the nervous system can be experienced locally close to the bite area or affect the nervous system directly. Venom from elapids and sea snakes can affect the nervous system directly. Cobra (Naja and other genera) and mamba (Dendroaspis) venom can act particularly quickly by stopping the breathing muscles, resulting in death without treatment. Initially, victims may have vision problems, speaking and breathing trouble, and numbness close to or distant to the bite site.
Muscle death: Venom from Russell’s vipers (Daboia russellii), sea snakes, and some Australian elapids can directly cause muscle death in multiple areas of the body. There can be local effect of muscle death (necrosis), or distant muscle involvement (rhabdomyolysis). The debris from dead muscle cells can clog the kidneys, which try to filter out the proteins. This can lead to kidney failure.
Eyes: Spitting cobras and ringhals (cobralike snakes from Africa) can actually eject their venom quite accurately into the eyes of their victims, resulting in direct eye pain and damage.
Spitting cobra bite. Many elapid bites result in little local swelling, but the spitting cobras are known for the amount of swelling and tissue damage they can cause.
Western diamondback rattlesnake (Crotalus atrox) bite. Rattlesnake bites can cause severe swelling, pain, and permanent tissue damage.
Copperhead (Agkistrodon contortrix) bite. These bites usually result in local pain and swelling but usually have less tissue loss than rattlesnake bites.
Timber rattlesnake (Crotalus horridus) bite.Pit viper bites can cause a leakage of blood cells out of the blood vessels, even on parts of the body away from the bite site. Note the significant bruising of the upper forearm and arm.