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TAIPAN GROUP


  • Common taipan Oxyuranus scutellatus
  • Inland taipan Oxyuranus microlepidotus

Though of restricted range, Taipans are the most dangerous of all snakes. This status ensures they are popular exhibits in zoos and amongst private keepers, so that bites may occur anywhere in Australia, not just within the natural range of these large snakes. There are two species in Australia: Oxyuranus scutellatus, the Taipan and Oxyuranus microlepidotus the Small-Scaled or Fierce snake (also known as the Inland or Western Taipan). Based on animal studies the Small-Scaled snake produces more lethal venom than any other terrestrial snake.

In the era pre-antivenom, Taipans had a >80% fatality rate. Their large size, large fangs, copious amounts of highly toxic venom place them at the top of any list of dangerous snakes globally. The venom contains potent pre- & post-synaptic neurotoxins, myotoxins, procoagulants and a variety of other, clinically less important toxins. Human envenoming causes pre- and postsynaptic flaccid paralysis, rhabdomyolysis, defibrination coagulopathy, and may also result in secondary renal failure, hyperkalaemia, cardiotoxicity or intracranial haemorrhage. The bite site is variable in appearance, from mild to moderate swelling, occasionally bruising, and is sometimes painful.

This information should be read in conjunction with the detailed background information on Australian snakebite.

Antivenom

Taipan or Polyvalent: starting dose 1 ampoule

Bite Site

90% effective bite, local mild pain, swelling and bruising

Principle venom effect

Predominantly paralysis, coagulopathy and myolysis

Taipans are restricted to the northern and NE mainland of Australia, but both inland and common taipans are popular amongst reptile keepers and quite a few exist both in reptile parks and in private collections with consequent bites. The taipan is one of the world's most dangerous snakes, and prior to the development of antivenom, nearly all cases were fatal. All taipan bites should be considered as potentially lethal, and require the most urgent attention. Because the problems they cause are complex, all cases should be managed in major hospitals, with full ICU, full laboratory facilities, and expert help from a Clinical Toxicologist/Toxinologist should always be sought.

The common taipan has a large rectangular shaped head, which is a pale cream colour anteriorly, and a cylindrical body that can be light brown, dark brown to black, coppery red or olive and red eyes. The inland taipan often has a dark coloured head, and a speckled brown body with black eyes. It is easily mistaken for a western brown snake.

Taipans have very powerful venom in large amounts delivered by large fangs (up to 12 mm for the common taipan). The venom has a wide spectrum of activity, including potent pre- and postsynaptic neurotoxins and procoagulants. Envenomation is usually accompanied by rapid onset of paralysis, defibrination type coagulopathy, and sometimes myolysis and renal failure. The patient may be so severely envenomed that intubation is needed within 1-2 hours of the bite. Bites by taipans are the only Australian snakebites where it may sometimes be justified to begin antivenom therapy before systemic envenomation is established.
NOTE: Gives positive result in the taipan tube of the Venom Detection Kit.

Preferred antivenom is CSL Taipan Antivenom. However, taipan antivenom is of similar volume and cost to polyvalent antivenom and it is therefore often more practical to stock and use polyvalent rather than taipan antivenom. In a metropolitan hospital, where access to taipan antivenom directly from CSL after hours is possible, it is best to use the specific antivenom for therapy.

REFERENCES


Currie BJ. Snakebite in tropical Australia, Papua New Guinea and Irian Jaya. Emerg.Med. 2000;12:285-94.
Mirtschin PJ, Crowe GR, Thomas MW. Envenomation by the inland taipan, Oxyuranus microlepidotus. Med.J.Aust. 1984;141(12-13):850-1.
Shea GM. The distribution and identification of dangerously venomous Australian terrestrial snakes. Aust.Vet.J. 1999;77(12):791-8.
Sutherland SK, Tibballs J. Treatment of snake bite in Australia. In: Sutherland SK, Tibballs J, editors. Australian Animal Toxins. 2nd ed. Melbourne: Oxford University Press; 2001. p. 286-342.
White J. Clinical Toxicology of Snakebite in Australia and New Guinea. In: Meier J, White J, editors. Handbook of Clinical Toxicology of Animal Venoms and Poisons. 1st ed. New York: CRC Press; 1995. p. 595-618.