Bitis gabonica
Bitis gabonica ( Gaboon Adder )  [ Original photo copyright © Dr Julian White ]
Family: Viperidae
Subfamily: Viperinae
Genus: Bitis
Species: gabonica
Common Names
Gaboon Adder , Gaboon Viper ( Eastern Race ) , Forest Puff Adder, Butterfly Adder , Swampjack
Local Names
Gaboenadder , Essalambwa , Mbishi , Mpili , Nkondambogo , Mpomo
Region
Sub-Saharan Africa
Countries
Angola, Benin, Burundi, Cameroon, Central African Republic, Democratic Republic of Congo, Republic of Congo, Equatorial Guinea, Gabon, Malawi, Mozambique, Nigeria, Rwanda, South Africa, Sudan, Tanzania, Togo, Uganda, Zambia, Zimbabwe, Cabinda
 
Taxonomy and Biology
Adult Length: 1.20 m
General Shape
Large in length and width, slightly depressed, extremely thick and heavy bodied ( fat in appearance ) snake with a short ( males ) to very short ( females ) tail. Can grow to a maximum of about 2.37 metres ( West Africa, smaller elsewhere ) with a girth up to about 47 cms. Head is large, broad, flat and triangular and very distinct from narrow neck. Snout is short with a pair of triangular nasal horns and canthus is distinct. Nostrils are directed upwards and outwards. Eyes are medium in size with vertically elliptical pupils. Dorsal scales are keeled ( except the first dorsal scale row ) with apical pits. Large fangs up to about 5.5 centimetres in length.
Habitat
Rainforest, secondary forest and forest fringes up to an elevation of about 2000 metres.
Habits
Nocturnal and terrestrial snake. Often found in leaf litter where its colour and pattern provide excellent camouflage. Although usually appearing fat and lazy it captures prey by ambush and strikes rapidly. If confronted it will huff and puff a lot, but rarely bites. Most bites occur from accidentally stepping on it.
Prey
Feeds mainly on large rodents and ground birds but will eat a variety of prey including amphibians. Adults can, and do take larger prey such as monkeys, hares, mongooses etc.
Species Map
Small (Approx 20k) version
 
Venom
Average Venom Qty
350 - 600 mg ( dried venom ), Phelps (1981) ( Ref : R000491 ).

450 - 600 mg ( dried venom ), Minton and Minton (1971) ( Ref : R000492 ).

400 - 1000 mg ( dried weight ), Broadley and Cock (1975) ( Ref : R000491 ).
General: Venom Neurotoxins
Not present
General: Venom Myotoxins
Not present
General: Venom Procoagulants
Fibrinogenases
General: Venom Anticoagulants
Possibly present
General: Venom Haemorrhagins
Zinc metalloproteinase
General: Venom Nephrotoxins
Not present
General: Venom Cardiotoxins
Present but not defined
General: Venom Necrotoxins
Possibly present
General: Venom Other
Unknown
 
Clinical Effects
General: Dangerousness
Severe envenoming likely, high lethality potential
General: Rate of Envenoming: 60-80% (estimate only)
General: Untreated Lethality Rate: Unknown but probably high
General: Local Effects
Marked local effects; pain, severe swelling, bruising, blistering
General: Local Necrosis
Common, moderate to severe
General: General Systemic Effects
Variable non-specific effects which may include headache, nausea, vomiting, abdominal pain, diarrhoea, dizziness, collapse or convulsions
General: Neurotoxic Paralysis
Only minor neurotoxicity reported
General: Myotoxicity
Not reported, unlikely to be significant
General: Coagulopathy & Haemorrhages
Very common, coagulopathy + haemorrhagins causing bleeding is major clinical effect
General: Renal Damage
Uncommon to rare, usually secondary effect
General: Cardiotoxicity
Common, cardiotoxicity is major clinical effect
General: Other
Shock secondary to fluid shifts due to local tissue injury is likely in severe cases
 
First Aid
Description: First aid for bites by Viperid snakes likely to cause significant local injury at the bite site (see listing in Comments section).
Details
1. After ensuring the patient and onlookers have moved out of range of further strikes by the snake, the bitten person should be reassured and persuaded to lie down and remain still. Many will be terrified, fearing sudden death and, in this mood, they may behave irrationally or even hysterically. The basis for reassurance is the fact that many venomous bites do not result in envenoming, the relatively slow progression to severe envenoming (hours following elapid bites, days following viper bites) and the effectiveness of modern medical treatment.
2. The bite wound should not be tampered with in any way. Wiping it once with a damp cloth to remove surface venom is unlikely to do much harm (or good) but the wound must not be massaged.
3. All rings or other jewellery on the bitten limb, especially on fingers, should be removed, as they may act as tourniquets if oedema develops.
4. The bitten limb should be immobilised as effectively as possible using an extemporised splint or sling; if available, crepe bandaging of the splinted limb is an effective form of immobilisation.
5. If there is any impairment of vital functions, such as problems with respiration, airway, circulation, heart function, these must be supported as a priority. In particular, for bites causing flaccid paralysis, including respiratory paralysis, both airway and respiration may be impaired, requiring urgent and prolonged treatment, which may include the mouth to mask (mouth to mouth) technique of expired air transfer. Seek urgent medical attention.
6. Do not use Tourniquets, cut, suck or scarify the wound or apply chemicals or electric shock.
7. Avoid peroral intake, absolutely no alcohol. No sedatives outside hospital. If there will be considerable delay before reaching medical aid, measured in several hours to days, then give clear fluids by mouth to prevent dehydration.
8. If the offending snake has been killed it should be brought with the patient for identification (only relevant in areas where there are more than one naturally occurring venomous snake species), but be careful to avoid touching the head, as even a dead snake can envenom. No attempt should be made to pursue the snake into the undergrowth as this will risk further bites.
9. The snakebite victim should be transported as quickly and as passively as possible to the nearest place where they can be seen by a medically-trained person (health station, dispensary, clinic or hospital). The bitten limb must not be exercised as muscular contraction will promote systemic absorption of venom. If no motor vehicle or boat is available, the patient can be carried on a stretcher or hurdle, on the pillion or crossbar of a bicycle or on someone's back.
10. Most traditional, and many of the more recently fashionable, first aid measures are useless and potentially dangerous. These include local cauterization, incision, excision, amputation, suction by mouth, vacuum pump or syringe, combined incision and suction ("venom-ex" apparatus), injection or instillation of compounds such as potassium permanganate, phenol (carbolic soap) and trypsin, application of electric shocks or ice (cryotherapy), use of traditional herbal, folk and other remedies including the ingestion of emetic plant products and parts of the snake, multiple incisions, tattooing and so on.
 
Treatment
Treatment Summary
Gaboon viper bites are likely to cause severe local & systemic envenoming rapidly, requiring urgent assessment & treatment. Fluid shift & shock may occur. Urgent fluid load, good wound care and antivenom are required. Antivenom is vital to treat major systemic effects. While compartment syndrome can occur, it must be confirmed by pressure measurement before considering fasciotomy. Beware any surgical intervention while venom haemorrhagins are active.
Key Diagnostic Features
Local swelling, blistering, necrosis + coagulopathy, bleeding, cardiotoxicity
General Approach to Management
All cases should be treated as urgent & potentially lethal. Rapid assessment & commencement of treatment including appropriate antivenom (if indicated & available) is mandatory. Admit all cases.
Antivenom Therapy
Antivenom is the key treatment for systemic envenoming. Multiple doses may be required.
Antivenoms
1. Antivenom Code: SAfSAI03
Antivenom Name: SAIMR Polyvalent Antivenom
Manufacturer: South African Vaccine Producers (Pty) Ltd
Phone: +27 11 386-6000; +27 11 386-6078
Address: Postal address
PO Box 28999
Sandringham 2131
Gauteng Province

Physical address
1 Modderfontein Road
Sandringham, Johannesburg
Country: South Africa
2. Antivenom Code: SAfSAIBK
Antivenom Name: SAIMR Snakebite Kit
Manufacturer: South African Vaccine Producers (Pty) Ltd
Phone: +27 11 386-6000; +27 11 386-6078
Address: Postal address
PO Box 28999
Sandringham 2131
Gauteng Province

Physical address
1 Modderfontein Road
Sandringham, Johannesburg
Country: South Africa
3. Antivenom Code: SAfAVC02
Antivenom Name: Polyvalent Snake Antivenom
Manufacturer: National Antivenom and Vaccine Production Centre
Phone: ++966-1-252-0088 ext 45626, 45637.
Address: P.O. Box 22490
Riyadh 11426
Country: Saudi Arabia
4. Antivenom Code: SAfIBM01
Antivenom Name: Antivipmyn Africa
Manufacturer: Instituto Bioclon
Phone: ++56-65-41-11
Address: Calzada de Tlalpan No. 4687
Toriello Guerra
C.P. 14050
Mexico, D.F.,
Country: Mexico
5. Antivenom Code: SAfICP07
Antivenom Name: Pan-African antivenom (EchiTAb-Plus-ICP)
Manufacturer: Instituto Clodomiro Picado
Phone: ++506-2511-7888
Address: Contiguo a la plaza de deportes,
Dulce Nombre de Coronado.
San José
Costa Rica
Country: Costa Rica
6. Antivenom Code: SAfVAC02
Antivenom Name: Polyvalent Snake Venom Antiserum
Manufacturer: VACSERA
Phone: (+20 2) 3761-1111
Address: 51 Wezaret El Zeraa St., Agouza, Giza, 22311
Country: Egypt
7. Antivenom Code: SAfSPF02
Antivenom Name: FAV-Afrique
Manufacturer: Sanofi-Pasteur
Phone: +33 (0)4 37 37 01 00
Address: 2, Avenue Pont Pasteur, CEDEX 07, Lyon 69367
Country: France
 
Images
Bitis gabonica ( Gaboon Adder ) [ Original photo copyright © Dr Julian White ]