In the ‘60s, my grandmother used to tell us not to put our hands in damp and dank places, even in the afternoon because snakes could be lurking inside.

Each year, at least 40,000 deaths result from snake bites in the world. Most cases are in Asia, where Burma has the highest rate with 15.4 deaths per 100,000 population per year. Accurate figures do not exist for the whole of Africa but there are probably at least 1,000 deaths in Africa.

About 60 species of snakes in Africa are potentially dangerous to man because they have fangs capable of injecting venom into the tissues according to Prof. E.H.O Parry. These species may be classified according to the structure and position of their fangs.

Colubridae Boignae are tree snakes. They have fixed rear fangs. They rarely bite humans. But deaths have been caused by the boomslang and the bird snake.

Thelotornis Kirt Landii. Note that scientific Latin names for snakes are important because anti-snake bite sera are often labelled with only Latin names to indicate their range of potency. The venom of these species causes generalized bleeding.

Elapidae like mambas, cobras, coral and garter snakes have short fixed front fangs. Their venoms are polypeptides which are rapidly absorbed into the circulation causing neurological and cardiac disturbances.

Hydrophiidae are sea snakes. These have very short fixed front fangs and the body is flattened from side to side. A single species Pelamis Platurus is found along the coast of Africa. The venom produces neurological symptoms by damaging the stated muscle. Sea snake bite is not a serious problem in Africa.

Viperidae are vipers and adders. These have long hinge fangs. Their venoms contain larger molecule proteins than do the Elipadae venoms. They are more slowly absorbed via lymphatic drainage and cause severe local tissue damage. some species, for example, the carpet viper, Echis Carinatus, cause severe generalized disturbances of blood coagulation.

Cored and rapid identification of the snake responsible for a bite is the most valuable guide to treatment. Identification is easier if the snake is killed and brought by the patient. In most cases, however, identification is by the early signs and symptoms of poisoning with venom.

Handle dead snakes carefully, because the fangs can still inject venom. The best indication that the snake is venomous is the presence of fangs, a pair of elongated teeth in the upper jaw placed either at the front (Elipidae, Viperidae) or at the back (Boiginae).

Cobra and mambas have large scales on the top of the head. They are long and then, with relatively long tails and are more uniformly coloured than vipers.

Vipers are shorter and thicker with short tails. Most have small scales on the top of the head and are a regularly repeated pattern along the back. The skin is extremely rough.

The boomslang is a green or brownish snake with ridged scales and very large eyes.

Some non-venomous snakes are very easily recognized. Pythons may grow larger than any of the poisonous snakes, sometimes more than 12 meters. They have distinctive blotchy patterns and very short tails.

I took time to describe various snake species because most of the anti-snake sera venom is labelled particularly and distinctively for easy remediation. The patient or witness should be asked about the length, thickness, colour markings, behaviour and habitat of the snake. Knowledge of local names for dangerous species may be very helpful.

Cobras usually rear up and spread their hoods before striking and unlike vipers, may not release the bite immediately. Two African species can spit their venom up to distances of three meters or more into the eyes of the victim. They are often found near water.

 Mambas are very long, thin, agile active snakes. They are usually found in wooded areas often in the branches of trees.

Vipers and adders are usually sluggish ground snakes, likely to be trodden on by the farmer. Many inflate their bodies when threatened. The carpet viper moves quickly and has a habit of side-winding, rubbing its coils together to produce a grating sound.

The boomslang is almost exclusively a tree snake. It may inflate its throat before striking.

Cobra and the puff adder are very widely distributed. Mambas seem to require the cover of thick trees, the gaboon and rhinoceros-horned vipers occur mainly in tropical rain purest and the carpet viper is found in dry savannah or desert.

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Snake bites are common among farmers and those who walk with exposed bare feet in rural areas. People walking through the bush at night, collecting firewood and hunting around burrows are at high risk.

The incidence of snake bites is highest at the start of the rainy season for the following reasons: people flock to their farms to sow their seed crops; burrow-dwelling snakes are driven into the open by flooding.

Snake venom is secreted by modified salivary glands and is mainly protein, a complex mixture of enzymes and toxins. The enzymes are digestive, some help the venom to spread through tissues and some may contribute to the lethal action of the venom.

 Some effects of snake venom may be due to the release of kinins, slow-reaching substance histamine 5-hydroxytryptamine, acetylcholine and other vaso-active compounds.

In cobra and mambas, the lethal toxins in their venom behave like polypeptides – they are relatively healed stable and dialyzable.

This explains their rapid absorption into the circulative and early neurotoxic effects.

A snake bite is always a terrifying experience. Symptoms and signs attributed to anxiety or even hysteria may confuse the clinical picture. Bites by venomous snakes do not always introduce venom and so may not cause any symptoms.

In diagnosis, it is important to find out how long ago the patient was bitten. After one-hour local pain and swelling should have developed, if viper venom has been injected.

  The patient should be asked to cough up sputum. Tooth sockets should be examined for early evidence of spontaneous haemorrhage caused by carpet viper venom.

A sample of the patient’s blood should be put in a plain tube – if it fails to clot within 20 minutes it gives useful evidence of a clotting defect from the snake bite.

The venepuncture site must be looked at to see whether bleeding has stopped or not and the urine should be examined for red cells. Neurological examination is important as it may show early signs of cobra and mamba poisoning.

When the patient arrives hospital after two or three hours of the snake bite if there are no signs of bleeding or fang marks, anti-venom should be withheld and the patient kept under observation for 24 hours.

If, however, the patient arrives at a hospital or primary Healthcare centre more than three hours after the bite and there are no signs of envenoming it is very unlikely that venom was introduced.

Anti-venom need not be given even if the snake was identified as a dangerous species. Allow the doctor to make the decisions.

 Although the following rules reduce the incidence of snake bites most are impracticable during the dangerous season for the people most at risk – farmers, hunters, collection and children

Wear shoes and long trousers;

Avoid walks through the undergrowth;

Avoid walking around at night without a light;

Be very cautious when collecting firewood and cutting long grasses.

Avoid exploring holes or crevices where snakes may lie

Avoid keeping domestic animals such as chickens near the house and keep down rats which in turn attract snakes.

Avoid handling live or dead snakes, many snake charmers and amateur and professional snake collectors have died of snake bites.