It is unarguable that snake, no matter how tiny it may appear, is feared by most people. A few snakes, with the rare exception of king cobras or black mambas, act aggressively toward humans without provocation. Many of the species are dangerous and capable of harming humans by injecting its poisonous substance (venom).
It has been estimated that about 1.8 million snakebites happen worldwide each year, causing between 20, 000 and 94,000 deaths. Snakebites are more common in tropical regions and in areas that are primarily agricultural in which a larger part of Nigeria falls into. 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.
Snakes are cold-blooded. Consequently, they are unable to increase their body temperature and stay active when it is cold outside. They are said to be most active at 25-32°C (77-90°F).
Occurrences have proven that people can usually survive venomous snake bites if they seek immediate medical attention. According to experts, all snakebites require medical attention, even if the snake is non-venomous. Also worthy of note is that proper wound care can help prevent infection and limit how severe the injury becomes.
There have been warnings never to assume that a snake is non-venomous without first consulting an expert. Researchers have shown that misclassification of snake species could be fatal and capable of putting the life of the victim on the line.
How snakes bite
After a three-year study of “poisonous and non-poisonous,” a group of medical team comprising veterinarians and zoologists in the United States America (USA), concluded that all bites from snake should be considered as venomous in order to guide against costly misconception.
The study, which was released in 2015, re-echoed the fact that snakes that inject venom use modified salivary glands. Venom is a modified form of saliva and probably evolved to aid in chemical digestion. Varying degrees of toxicity also make it useful in killing prey. 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.
The group added that snake venom is a combination of numerous substances with varying effects, which can be divided into four categories. They are cytotoxins that cause local tissue damage; hemotoxins, which is responsible for internal bleeding; while neurotoxins affect the nervous system; and cardiotoxins act directly on the heart.
The experts also revalidated the fact that apart from biting humans, they catch and swallow prey that include insects, birds, small mammals, and other reptiles, sometimes other snakes.
“Only about 400 of 3,000 snake species worldwide inject venom (a poison). Many snakes catch 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,” the study revealed.
Dangerous snake species
It has been discovered that two major families of snakes account for most venomous snakes dangerous to humans. The elapid family includes the cobras; the mambas; 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.
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.
However, it was also revealed that most species of the most widely distributed and diverse snake family, the Colubrids, lack venom that is dangerous to humans. There is also a warning that some species in this family, including the boomslang (Dispholidus typus), twig snakes (Thelotornis), the Japanese garter snake (Rhabdophis tigrinus), and brown tree snake (Boiga irregularis), could be dangerous. Other members of this family, including American garter snakes, king snakes, rat snakes, and racers, are harmless to humans.
Bites by venomous snakes result in a wide range of effects; from simple puncture wounds to life-threatening illness and death. Symptoms of a venomous snake bite can include swelling, pain, redness, and bruising around the bite area. Usually, people know right away if a snake has bitten them. However, these animals can strike quickly and disappear before people have time to react.
Venomous snakes have two fangs that deliver venom when they bite. A venomous snake bite will usually leave two clear puncture marks. In contrast, a non-venomous bite tends to leave two rows of teeth marks. It can be difficult to tell the difference between puncture wounds from venomous and non-venomous snakes. People should seek medical attention for all snake bites.
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. The typical symptoms of a venomous snake bite include: numbness of the face, especially in the mouth; dizziness; weakness; headaches; blurred vision; excessive sweating; fever; thirst; nausea; vomiting; diarrhoea; fainting; convulsions. The manifestations come in the following ways:
Local effects: Bites by vipers and some cobras 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 bleeding of internal organs such as the brain or bowels. 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: Venom from elapids and sea snakes can affect the nervous system directly. Cobra and mamba 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.
Muscle death: Venom from Russell’s vipers, sea snakes, and some Australian elapids can directly cause muscle death in multiple areas of the body. 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 (cobra-like snakes from Africa) can actually eject their venom quite accurately into the eyes of their victims, resulting in direct eye pain and damage.
When to seek medical care
Medical workers have repeatedly called for the need for any snakebite victim to quickly go to a hospital emergency department unless the snake is positively identified by an expert as non-venomous. Remember, misidentification of the snake species could be a fatal error.
Bites by non-venomous species require good wound care. Victims should receive a tetanus booster if they have not had one within the last five years.
Diagnosis of snakebite is made based on the history of the event. Identification or description of the snake would be helpful, because not all snakes are venomous, and because different kinds of anti-venom exist for different species of snakes.
But there is a clause in this regard in most hospitals across Nigeria, even the ones in urban area. For instance, in Australia, the doctor may use a kit to determine the specific type of snake. The doctor also looks for evidence of fang marks or local trauma in the area of the bite. Pain and swelling accompany many snakebites. Both the anti-venom and kit are said to be conspicuously missing in many Nigerian health centres.
The doctor will likely send blood and urine samples to the laboratory to look for evidence of bleeding, problems in the blood clotting system, kidney problems, or muscle death. These problems may not be initially apparent, but can have dire consequences if missed. The victim is monitored to look for worsening symptoms at the wound site, or worsening systemic symptoms in the breathing or cardiovascular systems.
The doctor treats breathing problems, shock, and, or immediately life-threatening injuries even before a full workup is complete. The wound needs to be examined and cleaned.
A victim with difficulty in breathing may need a tube placed in his or her throat and a ventilator machine used to help with breathing. People who are in shock require intravenous fluids and possibly other medicines to maintain blood flow to vital organs.
The doctor gives anti-venom to victims with significant symptoms if appropriate and available. This therapy can be lifesaving or limb-saving. Anti-venom can occasionally also cause allergic reactions or even anaphylactic shock, a life-threatening type of shock requiring immediate medical treatment with epinephrine and other medications.
Anti-venom can also cause serum sickness within five to 10 days of therapy. Serum sickness causes fevers, joint aches, itching, swollen lymph nodes, and fatigue, but it is not life threatening.
Even victims without significant symptoms need to be monitored for several hours, and some people need to be admitted to the hospital for overnight observation.
A tetanus shot is required if the victim has not had one within five years. Some wounds may require antibiotics to help prevent infection.
Rarely, the doctor may need to consult a surgeon if there is evidence of compartment syndrome. If treatment with limb elevation and medicines fails, the surgeon may need to cut through the skin into the affected compartment, a procedure called a fasciotomy. This procedure can relieve the increased limb swelling and pressure, potentially saving the arm or leg.
There are said to be a rare complication in very swollen limbs – compartment syndrome. Limbs are divided into compartments of muscles, blood vessels, and nerves. Severe swelling can cut off the blood circulation to a compartment. When the circulation is cut off, the victim usually has severe pain and numbness. Later, the limb may get white and cold. If not treated in time, the limb may need to be amputated.
A snakebite victim who has been released from the hospital is advised to return to medical care immediately if he or she develops any worsening symptoms, especially trouble breathing, change in mental status, evidence of bleeding, worsening pain or worsening swelling.
“Someone who has received anti-venom treatment for snakebite should return to medical care if any signs of serum sickness develop (fever, muscle or joint aches or swelling, hives). This complication usually occurs within five to 10 days after administration of anti-venom,” an American family physician, Paul Wellington has said.
He said that a snakebite victim (particularly a rattlesnake bite) should, for the first few weeks, warn his or her physician of these signs before any routine or emergency surgery. He added that some snake venoms can cause difficulty in blood-clotting for a week or more after the bite.
The snake is almost always more scared of you than you are of the snake, therefore, giving the snake the opportunity to escape prevents most bites. Snakes usually hibernate in dark or bushy areas. Some could be found in holes, on trees and gardens.
Do not attempt to handle, capture, or tease venomous snakes or snakes of unknown identity. Snakes will not bite humans unless they feel threatened, so leaving them alone is the best strategy for preventing a bite.
Snakebites are often associated with excessive alcohol use. Alcohol intake can weaken your inhibitions, making it more likely that you might attempt to pick up a snake. Alcohol also decreases your coordination, increasing the probability of a mishap.
If you are outdoors or in areas where snakes are common, you can help prevent significant bites by wearing boots. Long pants can reduce the severity of a bite. When in snake prone areas, be cautious where you place your hands and feet, and never walk barefoot after dark.
If your occupation or hobby exposes you to dangerous snakes on a regular basis, preplanning before a potential bite may save your life. Since not every physician is familiar with snakebites and not every hospital has or knows how to obtain anti-venom, providing information regarding the type of snake, type of venom, and the procurement and use of anti-venom can help the medical staff treat you.
Despite the fact that there may be as many as 8,000 bites by venomous snakes in the US, there are fewer than 10 deaths, and most of these fatal cases do not seek care for one reason or another. It is rare for someone to die before they are able to reach medical care in America, but this might not be so in most developing countries where access to health facilities is limited. The availability of emergency medical care and, most important, anti-venom can affect how well the victim does.
In order to guide the expert in treatment procedure, victims are expected to note the snake’s appearance. Also, while waiting for medical help: Move the person beyond striking distance of the snake; and have the person lie down with wound below the heart; keep the person calm and at rest, remaining as still as possible to keep venom from spreading. Other interventions are to cover the wound with loose, sterile bandage; remove any jewelry from the area that was bitten; and remove shoes if the leg or foot was bitten.
There are many misconceptions about first aid for snake bites. The following checklists describe what to avoid doing after a snake bite: Do not cut into the bite wound; do not wrap a cloth above the wound to restrict blood flow; do not apply ice to the wound; do not suck the venom from the wound; do not use a suction device to remove venom; and do not give a person medication unless a healthcare professional gives this instruction.