This document is designed to aid doctors and other medical personnel in the diagnosis, first aid treatment, and further management of snakebite injures related to the local risk in Sadiola, Mali. It is not a definitive text, merely a guide. The appropriate treatments for individual snakebites should be gleaned from the available references and expert opinion sought as necessary.

Risks to agricultural and remote workers are relatively high with some 400 different species of snake occurring in the African continent. That having been said only 90 of these has venomous bites, and of that 90 only 30 different species are known to have caused death. Thus over 80% of African snakes are harmless.

Snakes by their very nature are predators and prey on small mammals and other pests. Simple precautions when in the field can alleviate problems before they arise. Most snakes’ bites occur below or around the ankle, therefore good quality strong boots should be worn. Common sense should prevail and the avoidance of snakes given priority. The adage "look before you leap" is entirely appropriate when discussing snakes. Avoid poking around in dark holes and be aware snakes like to sunbathe on paths and concrete particularly in the late evening where residual heat is present.

In summary the snake is often more frightened of you than you are of it, give it a wide berth and allow to go about its business!

Stay Calm, put the casualty immediately at rest. Do not allow walking or moving around.

Explain and reassure that statistically very few people die from snakebites and most recover with little or no treatment at all.

Apply a pressure bandage to the whole limb. Keep the limb still work from the bite site up the limb. If no crepe bandages are available then use strips of cloth or clothing. As venom is transmitted by lymphatic systems this will decrease the likelihood of venom entering the blood stream.

Splint the limb as you would a fracture.

Remove to the medical facility as a stretcher case, preferably notifying the clinic by radio beforehand.

Do not under any circumstances, suck the wound, open the wound by cutting, or use any form of tourniquet. All these practices are detrimental to the patient.

• Begin immediate intensive monitoring including

• Cardioscope
• Vital Signs
• Oxygen Saturation
• Carry out a brief but thorough physical examination.
• Take a complete History
• Mark the area of swelling with ink and monitor

• Be prepared to resuscitate and treat for anaphylaxis if necessary

In general, the most effective medical treatment for a life threatening snakebite is the intravenous administration of snakebite anti venom. However in non-life threatening cases or for snakes not covered by the serum symptomatic treatment should be carried out. For life threatening cases where neurotoxic venom is suspected (big cobra or mamba) resuscitation may be necessary. For life threatening cases involving cytotoxic venom (puff adder, vipers and spitting cobra’s) or a case where clotting abnormalities are noted blood volume must be maintained.

It should however be noted that in most cases only mild symptoms will prevail and symptomatic treatment will be the order of the day. If no abnormalities have been detected within six hours of the bite then it is usually safe to send the patient home, or continue monitoring at a lesser degree.

Shock and Fear are prevalent after a snakebite, it may be necessary to give the patient a placebo to alleviate these. The medical staff can then look for "genuine" symptoms.

• Bleeding – Bites and stings from Arthropods rarely bleed.
• Local Pain, swelling and discolouration. Swelling usually means a viper bite.
• Tenderness of regional lymph nodes at one hour plus
• Bite marks approximately 1cm apart
• Dyspnea, and paralysis (later symptoms)

Laboratory procedures should include urinalysis, Haemoglobin, haematocrit, Leucocyte count and blood grouping. Coagulation profiles should be done in cases of viper bites.

In cases where lab facilities are not available a small blood sample taken in a clean, dry and non-additive tube should be monitored for clotting time and quality.

ECG’s may be of use in cardiovascular instability.

Anti venom in itself can cause more problems than the initial snakebite, care should be taken when deciding to administer anti venom, due to the high incidence of anaphylactic reactions to the anti venom itself. The following paragraphs give an indication of when to administer anti venom. If there is any element of doubt one of the international poisons centres should be contacted for advice.

If there are obvious signs of a severe adder bite. Extensive and increasing swelling, 15cm or more beyond the site in less than 2 Hours. Swelling in the arm extends to the chest wall or swelling of the foot extends above the knee.

Systemic signs such as blood stained saliva, hypotension or markedly unstable blood pressure, abnormally long clotting times or external bleeding are absolute indicators for anti venom.

Initial or progressive neuromuscular paralysis demands early administration of anti venom

Severe swelling where a spitting cobra bite is suspected

Be much readier to give anti venom to children or people with a small body mass

Snake bite anti venom should be given at room temperature in a saline drip. As previously mentioned the use of anti venom can carry severe risks to the patient and the use of such anti venom "just in case" is completely inadmissible.

1. Ensure monitoring is carried out
2. Gain IV access
3. Pre load with Antihistamine Phenergan 1mg/kg up to a maximum of 100mg
4. Dilute 50ml of Ipser Africa in 1000ml of Normal Saline
5. Open drip and monitor closesly

Determine and remove the cause – i.e. stop giving anti venom

0.5 – 1.0 mg of Adrenaline diluted in 10 ml of normal saline given slow IV.

0.25 mg diluted in 10 ml of Saline

Consider also anti histamines and hydrocortisone.

Clinical Guidelines – "Medicins Sans Frontieres"

Dangerous Snakes of Africa - Spawls and Branch

Principles of Internal Medicine – Harrisons

According to the references, Mali has sixteen confirmed dangerous snakes, with the possibility of one more. Evidence is weak but the seventeenth snake is thought to exist in Mali and there have been unsubstantiated sightings. Of the seventeen snakes one is non-venomous but still dangerous, nine fall into the venomous but not normally fatal category, and the final seven are considered venomous and can be fatal. It should be understood that although they are categorised as being possibly fatal often the fatalities consist of the very young, the old or the infirm so when assessing this category this should be taken into account

The table below categorises the snakes by type in the following categories along with their common English names and Latin names. A brief summary of each snake then follows the table. It should be stressed at this point that I am no snake expert the information I have laid out is taken purely from the available literature

• Non Venomous but considered Dangerous
• Venomous considered not normally to be fatal
• Venomous considered to be possibly fatal in certain circumstances

I have also tried where possible to note the effects of the venom either as Neurotoxic, Haemotoxic, or those that affect blood coagulation properties.

• NT =Neurotoxic
• HT =Haemotoxic
• CP =Venom’s which effect coagulation properties of blood
• NK = Not Known

The largest of all snakes in Africa, averaging 3-5 meters in length, but can reach 9 meters. Triangular head covered in irregular shaped scales, with a large spearhead marking on the crown, and dark and light bands radiating from the eye to the lips. The body is grey green or grey brown with dark brown black edged bands that may form isolated blotches on the flanks. The belly is white with dark speckles.

Mainly nocturnal though may bask particularly when shedding. It favours rock caves and hollow tress and is very aggressive and will bite readily.

Although non-venomous its bite can inflict serious injury resulting in sutures. A large python is easily capable of killing by constriction and hence is considered dangerous. Crush wounds are not normally present and death is caused by asphyxiation.

Anti-venom is unnecessary as the species is non-venomous however the patient is at risk from infection from the bite and antibiotic and tetanus cover should be considered.

A large elongate snake that may exceed 2 meters in length, it has a very short head with large round eyes. It has diagonal rowed scales along its length. Colouration is variable and varies from region to region.

Prefers trees and inhabits most wooded habitats.

Although venomous it is normally an inoffensive snake and will usually give ample warning before biting. Serious envenomation usually requires the snake to chew for a few seconds. There is usually little immediate reaction to the bite. Usually after 24 hours and up to and including 3-5 days general bleeding tendency develops.

Polyvalent anti venom is non-effective and should not be used. Specific anti venom is sometimes available from the South African Institute of Medical Research. Bites are normally rare and usually follow provocation. Clotting factors and screening of blood coagulation is important.

A medium sized slender, fast moving burrowing snake. Usually black greys in colour occasionally black brown. Usually prefers dry or moist savannahs and forest

Very little is know of its venom, however recorded bites have resulted in mild swelling, lymphadenopathy and have settled after an uneventful few days. No existing venom is available to neutralise Atracaspis venom and therefor anti venom is contraindicated. Treatment should be conservative and include analgesia and antibiotic cover.

A slow moving medium sized snake, juveniles can be slender though adults are usually more thicker set. Maximum size is 60cm though 30-50 is more usual. Generally dark brown, grey pink, or black in colour. The underside is usually lighter.

Generally prefers savannah and forest. Common in Western Mali.

Although venomous, victims only usually experience pain and local swelling. Usually reaching a peak in the first 24 hours. Some victims have reported tender lymph nodes and fever. No necrosis has been reported. No existing venom is available to neutralise Atracaspis venom and therefor anti venom is contraindicated.

Juveniles can be slender though adults are remarkably stout. Fast moving especially at night. One of the largest burrowing asps it can reach 1.1meters in length. However specimens in West Africa are usually not larger than 75cm. Colouring is normally shiny black, purple black, deep grey or very dark brown, occasionally it has a white tail.

Injected venom tends to me more than its brother asps. Numerous bites have been recorded but only usually result in pain and local swelling. Tender lymph nodes and fever have also been reported. Small areas of necrosis often appear around the bite site. In some cases nausea, vomiting and diarrhoea may appear. In one or two severe cases Dyspnea may occur. Three fatalities have been reported but these appear to be in exceptional circumstances.

The Black Mamba is the snake where its existence in Mali is unclear. It is a long slender fast moving snake with a long narrow coffin shaped head. It is usually light grey or olive brown. The inside of its mouth is usually blue black. Generally its underside is cream or ivory in colour or pale green. It has a cylindrical body with a long thin tail. Maximum size is 3.5 meters though more usually it is 2-3 meters.

Equally at home on the ground or in the trees, it climbs and moves quickly. It is most active around dawn and dusk and often has semi-permenent homes preferring holes and caves. It is generally found in low altitude wooded areas.

Normally when provoked it can inject lethal doses of venom. The venom is both neuro and Haemotoxic with death often occurring from respiratory failure. In the late 1960’s mamba bites were almost always fatal. Now patients reaching hospital have a good chance of survival when treated with aggressive anti venom therapy. However much anti venom is often needed, and patients often need supplemental oxygen and ventilation.

A small glossy snake, neither fat nor thin with a short head and eyes set well forward. Usually it is 30-50 cm in size but can reach sizes of up to 70 cm. Adults have fine white bands and in juveniles these tend to be white or yellow on a grey or black body slowing changing as the snake ages.

This snake has a wide choice of habitats and often gets in to forest clearings. They are also common in grasslands at low altitudes. Normally they are terrestrial and slow moving usually more prominent at nights.

Not much is known of its venom however it is presumed to be neurotoxic and as with all garter snakes its is unlikely to be life threatening. No specific anti venom exists and bites should be treated conservatively with analgesia and antibiotic cover.

A big thick bodied cobra with a broad head and fairly large eye. Maximum size is usually 2.5 meters though they average 1.3 – 1.8 meters. Colour varies but they are usually brown or grey and yellow and cream underneath. Often the African varieties can appear to be banded.

It prefers savannah and woodland it is clumsy but fast moving. It is active both night and day but prefers to bask during the day.

It has an extremely potent neurotoxin and when it strikes it often injects far more than the lethal dose for humans. Bits from large cobras usually involve a progressive flaccid paralysis leading to respiratory distress and eventual death. Initial symptoms include a burning pain and a slow developing swelling, if systemic symptoms appear during the first hour the bite is expected to be very serious.

Treatment involves the usual first aid along with aggressive anti venom therapy.

A fairly big thick bodied cobra with a large head and a large round eye, slightly larger than its Egyptian cousin. Colours vary from habitat to habitat It is generally a terrestrial snake but a fast graceful climber.

It is a snake of the forest and woodland. It is also one of the few of the cobra family that can live at relatively high altitudes.

Little is know of its venom however it is expected to be an extremely potent neurotoxin. It is thought that the venom will induce obvious neurological symptoms. That having been said there have been relatively few reported cases which suggests the snake is adept at avoiding humans.

Treatment involves the usual first aid along with aggressive anti venom therapy

A small red brown cobra, of average thickness with a small head and a large eyes. Maximum size is around 1 meter. Usually red brown or warm brown, occasionally maroon in colour. Often light brown underneath and possibly banded at the neck.

This snake is mostly terrestrial but will climb low bushes. It is fast moving and alert and active both day and night Prefers dry savannah and dusty areas.

There are no recorded case histories for the species and it is not known if bites are fatal. It is important when dealing with spitting cobras that any venom is thoroughly washed out of the eye, rotating the eyeball. Anaesthetics and analgesic’s may be used.

This is an usually variable snake making identification difficult They are usually banded and have the common flared head of the cobra family.

It is terrestrial, quick moving but can climb when needs be. It is mostly active at night, but will hunt and bask in the day.

Venom in the eye is the most common result of an encounter with this snake. Causing pain and temporary loss of vision. It will also bite readily, symptoms appear to be localised including pain swelling, extensive local necrosis and even the loss of digits and limbs.

It is important when dealing with spitting cobras that any venom is thoroughly washed out of the eye, rotating the eyeball. Anaesthetics and analgesic’s may be used. For bites anti venom therapy may be needed. A specific anti venom exists for this snake.

A stout snake with a large flat head and large round nostrils. Colour varies from region to region but is usually yellow brown or orange brown, with chevron shaped bars.

It is terrestrial and basically nocturnal, but it will climb sturdy bushes to bask. It is normally sluggish or slow due to its fat body, but can move deceptively quickly when trying to escape. It prefers open grassland with low shrub vegetation.

Following a bite pain and swelling may be extensive often with bruising and painful lymph glands. Well treated cases rarely develop necrosis but it may develop from poorly treated cases or secondary infection..

Generally the treatment is conservative, but if large scale swelling develops then vigour anti venom therapy should be used and blood volumes maintained.

A short stout viper with a broad triangular head, thin neck and often has a small horn above each eye.

It is terrestrial and slow moving it generally is not known to climb and prefers desert and dry rocky areas. It is nocturnal and is generally not seen during the day.

Bites usually involve swelling and bleeding, necrosis may occur. Nausea and vomiting are also common symptoms. Fatalities are infrequent. In serious bites the appropriate anti venom should be considered.

A fat little viper with a broad triangular head and tiny eyes

It is terrestrial and slow moving it generally is not known to climb and prefers desert and dry rocky areas. It is nocturnal and is generally not seen during the day.

Little is known of its venom but bites usually involve swelling and bleeding, necrosis may occur. Bites should be treated conservatively with antibiotics and analgesia in serious bites the appropriate anti venom should be considered.

A small robust snake a pear shaped head and thin neck, with distinctive white spots.

It prefers mostly savannah but is unusual amongst carpet vipers as it likes woodland as well. Terrestrial but will climb stout bushes to avoid hot or wet surfaces.

The venom has a procoagulant action, bites from this species are a major medical risk especially in rural areas. There have been many confirmed bites often producing swelling, blistering and necrosis spontaneous systemic bleeding has also occurred.

The venom tends to be slow acting thus delaying the onset of symptoms, bites should be treated with the correct anti-venom and coagulation properties monitored

A small robust snake a pear shaped head and thin neck, triangular flank markings and a distinctive white belly. It prefers mostly savannah, but is common in most hot dry areas. Terrestrial but will climb stout bushes to avoid hot or wet surfaces.

Little is known of the venom but it is expected to act in a similar manner to the other carpet vipers. Treatment should involve first aid measures and monitoring, anti venom therapy may be needed in severe cases

A small night adder, coloured vivid green. It has prominent eyes and in juveniles it has a distinctive white V shape behind its head.

It is slow moving and terrestrial, it is also secretive but can strike quickly when disturbed. Despite its name it is often active during the day, often basking.

Little is known of the venom but it is not thought to be fatal, bites should be managed conservatively with analgesia and elevation.

Ian R Sharpe ‘Mar 99

Remote Support Medical Officer

AEA SOS International