Cambodia - Very Venomous Snakes Found - Ophiophagus Hannah

Ophiophagus hannah ( King Cobra )

Original photo copyright © Dr Julian White

Family: Elapidae

Subfamily: Elapinae

Genus: Ophiophagus

Species: Hannah

Common Names: King Cobra , Hamadryad , Jungle Cobra

Local Names: Taw-Gyi Mwe Haut , Yanjing Wang She , Ular Tedong Selar , Ular Kunyet Terus , Ular Tedong Belalang , Ular Anang , Oraj Totok , Ular Tedung , Tomumuho , Mantakah , Belalang

Region: Indian Sub-continent + North Asia + Southeast Asia

Countries: Bangladesh, Bhutan, Brunei, Cambodia, China, Hong Kong, Indonesia, India, Laos, Malaysia, Myanmar, Nepal, Philippines, Singapore, Thailand, Vietnam, Tibet

Ophiophagus hannah ( King Cobra ) Original photo copyright © Dr Julian White

Taxonomy and Biology

Adult Length: 2.00 m

General Shape: Very large in length, tapering, slender bodied snake, withmedium to moderately long tail. Capable of extending the neck region into a long and narrow hood. World's largest venomous snake. Can grow to a maximum of about 5.85 metres ( but rarely found to exceed 4.30 metres ). Head is moderately short, flattened, moderately distinct from neck, with a broad, rounded snout and an indistinct canthus. Eyes are medium in size with round pupils. Dorsal scales are smooth and oblique with anterior vertebral row and outer 2 scale rows enlarged, posterior portion of body often with the middle 3 rows enlarged. Dorsal scale count ( 19 or 17 ) - 15 - 15 ( 13 ).

Habitat: Wide range of habitats. Jungle and primary and secondary forest, woodlands, open fields and foothills at elevations up to about 1800 metres.

Habits: Cannibalistic, terrestrial and diurnal. Non-aggressive and will escape to cover if disturbed but does have a reputation for aggression when brooding. Fearless snake which will not hesitate to stand its ground If provoked or cornered. It will raise its forebody high off the ground and spread its hood and make a growling-like noise in defense.

Prey: Feeds almost entirely on snakes, occasionally lizards.

Ophiophagus hannah ( King Cobra ) Original photo copyright © Dr Wolfgang Wuster - Thailand

Venom

General: Venom Neurotoxins	Postsynaptic neurotoxins
General: Venom Myotoxins	Probably not present
General: Venom Procoagulants	Probably not present
General: Venom Anticoagulants	Probably not present
General: Venom Haemorrhagins	Probably not present
General: Venom Nephrotoxins	Probably not present
General: Venom Cardiotoxins	Primary cardiotoxin
General: Venom Necrotoxins	Possibly present
General: Venom Other	Unknown

Clinical Effects

General: Dangerousness	Severe envenoming likely, high lethality potential
General: Rate of Envenoming	>80%
General: Untreated Lethality Rate	50-60%
General: Local Effects	Marked local effects; pain, severe swelling, necrosis
General: Local Necrosis	Uncommon but can be 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	May cause moderate to severe flaccid paralysis
General: Myotoxicity	Does not occur, based on current clinical evidence
General: Coagulopathy & Haemorrhages	Does not occur, based on current clinical evidence
General: Renal Damage	Does not occur, based on current clinical evidence
General: Cardiotoxicity	Venom of some studied specimens contains an unusual three-finger cardiotoxin that, unlike other elapid cardiotoxins, induces bradycardia, not tachycardia.
General: Other	Unknown

First Aid

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.

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.

Treatment

Treatment Summary: Bites can cause both local tissue injury and systemic effects, principally flaccid paralysis. Treatment is therefore twofold; good wound care and control of secondary infection, plus watch for flaccid paralysis. If severe paralysis present, with respiratory failure, requires intubation & ventilation. Specific antivenoms available, which should be given at first sign of developing paralysis.

Key Diagnostic Features: Local pain, swelling, blistering, necrosis ± flaccid paralysis

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: SAsCRI01

Antivenom Name: Polyvalent Anti Snake Venom Serum

Manufacturer: Central Research Institute

Phone: ++91-1-792-72114

Address: Kasauli (H.P.) 173204

Country: India

2. Antivenom Code: SAsTRC03

Antivenom Name: King Cobra Antivenin

Manufacturer: Science Division, Thai Red Cross Society

Phone: ++66-2-252-0161 (up to 0164)

Address: Queen Saovabha Memorial Institute

1871 Rama IV Road

Pathumwan

Bangkok 10330

Country: Thailand

3. Antivenom Code: SAsVRU06

Antivenom Name: Ophiophagus hannah Antivenom

Manufacturer: Venom Research Unit

Address: University of Medicine and Pharmacy

Ho Chi Minh City

217 An Duong Vuong Q5

Country: Vietnam

4. Antivenom Code: SAsSII01

Antivenom Name: SII Polyvalent Antisnake Venom Serum ( lyophilized )

Manufacturer: Serum Institute of India Ltd.

Phone: +91-20-26993900

Address: 212/2, Hadapsar,

Off Soli Poonawalla Road,

Pune-411042. India

Country: India

Source: Clinical Toxinology Resources