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![Acanthophis laevis ( Smooth scaled Death Adder ) [ Original photo copyright © David Williams ]](images/snakes/SNP27861.jpg)
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Family: Elapidae
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Subfamily: Elapinae
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Genus: Acanthophis
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Species: laevis
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Common Names
Smooth-scaled Death Adder , New Guinea Death Adder , Eastern Death Adder
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Region
Australia + New Guinea + Indonesia
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Countries
Australia, Indonesia, Papua New Guinea
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Taxonomy and Biology
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Adult Length: 0.50 m
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General Shape
Small, short, stout, stumpy bodied snake with a medium to moderately short, slender, rat-like tail terminating in a sharp, soft and curved spine. Can grow to a maximum of 0.9-1.0 metres. Viper-like in appearance with a broad, triangular head, with raised horn-like supraocular scales, pronounced brow ridge and head is distinct from the very narrow neck. Eyes are medium in size with vertically elliptical pupils. Body and head scales are smooth or weakly keeled without apical pits. Dorsal scale count 21 (19 or 23) - 21 (19 or 23) - 17 (19).
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Habitat
Death adders occur in a wide range of habitats including lowland grasslands and savannahs, sago swamps, monsoonal forests, woodlands, rainforest, coffee, tea and cocoa plantations, village gardens, highland grasslands and other montane environments. These ground dwelling snakes can be common in any area with abundant leaf litter, grass trash or other ground cover in which they can hide. They often occur around forest margins, or on the periphery of garden plots, and near the sides of walking tracks: all areas of filtered sunlight and abundant lizard prey.Highland New Guinea : Monsoon jungle and rainforest, upland grassland valleys and very often encountered in coffee plantations.
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Habits
Generally nocturnal, these snakes usually sit under cover during the day, often close to pathways along which small animals (and people) regularly travel. If disturbed (by the burning of grass for example) they may move around during the day. Often seen crossing roads and paths at night, especially at dusk when people are returning home from the garden or bush. Although this represents one danger period for contact with this snake, many bites occur in daytime when people step on the sleeping snake, or touch it as they reach down to pick up something.
Death adders are unique among PNG snakes in their reliance on a 'sit and wait' ambush feeding strategy, which means that they will remain motionless on the ground even when approached very closely. These inoffensive snakes become a significant snakebite threat because of this behaviour. While most snakes will flee from an approaching human, death adders rely on remaining motionless to avoid detection, but if touched will strike reflexively.
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Prey
Predominantly small ground-dwelling lizards, frogs and occasionally small rodents or ground birds that are attracted to wriggling of the snake's grub-like tail.
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Venom
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General: Venom Neurotoxins
Pre- & Post-synaptic neurotoxins
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General: Venom Myotoxins
Present but possibly not clinically significant
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General: Venom Procoagulants
Not present
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General: Venom Anticoagulants
Present but not clinically significant
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General: Venom Haemorrhagins
Not present
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General: Venom Nephrotoxins
Not present
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General: Venom Cardiotoxins
Not present
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General: Venom Necrotoxins
Not present
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General: Venom Other
Not present or not significant
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Clinical Effects
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General: Dangerousness
Severe envenoming possible, potentially lethal
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General: Rate of Envenoming: 40-60%
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General: Untreated Lethality Rate: 50-60%
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General: Local Effects
Local pain & swelling
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General: Local Necrosis
Not likely to occur
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General: General Systemic Effects
Variable non-specific effects which may include headache, nausea, vomiting, abdominal pain, diarrhoea, dizziness, collapse or convulsions
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General: Neurotoxic Paralysis
Very common, flaccid paralysis is major clinical effect
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General: Myotoxicity
Slight rise in CK common, but major myolysis not reported
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General: Coagulopathy & Haemorrhages
Slight prolongation of prothrombin time reported, but major coagulopathy not likely
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General: Renal Damage
Unlikely to occur
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General: Cardiotoxicity
Unlikely to occur
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General: Other
Unknown
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First Aid
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Description: First aid for bites by Elapid snakes which do not cause significant injury at the bite site (see Comments for partial listing), but which may have the potential to cause significant general (systemic) effects, such as paralysis, muscle damage, or bleeding.
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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. For Australian snakes only, do not wash or clean the wound in any way, as this may interfere with later venom detection once in a hospital.
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. If the bite is on a limb, a broad bandage (even torn strips of clothing or pantyhose) should be applied over the bitten area at moderate pressure (as for a sprain; not so tight circulation is impaired), then extended to cover as much of the bitten limb as possible, including fingers or toes, going over the top of clothing rather than risking excessive limb movement by removing clothing. The bitten limb should then be immobilised as effectively as possible using an extemporised splint or sling.
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.
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Treatment
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Treatment Summary
Death adder bites have a high potential for major envenoming (paralysis), so all cases require urgent assessment. At first sign of developing paralysis, give antivenom.
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Key Diagnostic Features
Local pain + flaccid paralysis
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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.
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Antivenom Therapy
Antivenom is the key treatment for systemic envenoming. Multiple doses may be required.
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| 1. Antivenom Code: SAuCSL07
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Antivenom Name: Death Adder Antivenom
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Manufacturer: CSL Limited
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Phone: ++61-3-9389-1911
Toll free: 1800 642 865
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Address: 45 Poplar Road
Parkville
Victoria 3052
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Country: Australia
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| 2. Antivenom Code: SAuCSL12
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Antivenom Name: Polyvalent Snake Antivenom ( Australia - New Guinea )
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Manufacturer: CSL Limited
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Phone: ++61-3-9389-1911
Toll free: 1800 642 865
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Address: 45 Poplar Road
Parkville
Victoria 3052
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Country: Australia
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