GENERAL
This animal usually weighs from 10 to 100g. Its span, with tentacles extended is from 2 to 20 cm, but usually less than 10 cm. It is found in rock pools and clumps of cunjevoi, at low tide. Its colour is yellowish-brown with ringed markings on the tentacles and striations on the body. These change to a vivid iridescent blue when the animal becomes angry, excited, disturbed or hypoxic. It may also occur when feeding. The heavier specimens are more dangerous. Handling these attractive creatures has resulted in death within a few minutes. Many such incidents have probably escaped detection by the coroner. Autopsy features are non-specific and the bite fades after death. The toxin (masculo-toxin) is far more potent than any land animal. Analysis of the posterior-salivary extracts demonstrates a hyaluronidase and cephalotoxins of low molecular weight (probably greater than 500). These have similar effects to tetrodotoxin and saxitoxin. The effects are that of a neurotoxin and a neuromuscular blocking agent. It is not curare-like, and it not influenced by neostigmine and atrophine, at least during the early phase. Hypotension accompanies respiratory depression.

CLINICAL FEATURES

LOCAL. Initially the bite is almost painless, and may go unnoticed. The 1cm circle of blanching become ceddematous and swollen in 15 minutes. It then becomes haemorrhagic, and resembles a blood blister. If the patient survives the next hour, he notices a local stinging sensation for approximately 6 hours. A serious bloody discharge may follow. Local muscular twitching may persist for some weeks.

GENERALIZED. A few minutes after the bite, a rapid painless paralysis dominates the clinical picture which progresses in this order;
(1) Abnormal sensations (numbness, fullness) around mouth, neck, head.
(2) Nausea and/or vomiting may occur.
(3) Breathing difficulties. Dysponea with rapid, shallow and stertorous respirations leading to apnoea, asphyxia and cyanosis (i.e. suffocation).
(4) Visual disturbances. Involvement of the eye muscles results in double vision and ptosis. Ocular paralysis results in a fixed dilated pupil.
(5) A difficulty in speech and swallowing.
(6) Generalized weakness and difficulty with co-ordination progresses to complete paralysis.
(7) The duration of paralysis is between 4 and 12 hours but weakness and inco-ordination may persist for another day. The patient's conscious state is initially normal even though he may not be able to open his eyes or respond to his environment. The respiratory paralysis (causing hypoxia and hypercapnoea) finally results in unconsciousness and then death, often within minutes of the commencement of symptoms, unless resuscitation is continued.
(8) Cardiovascular effects of hypotension and bradycardia are noted in severe cases.

There may be a termination at any stage of the above clinical sequence, i.e. the effects may cause the local reaction, a partial paralysis, or proceed in a complete paralysis and death. Less severe bites may result in generalised and local muscular contractions (spasms) which may continue intermittently for 6 hours or more. This occurs with a depersonalisation, paraesthesia, weakness and exhaustion.

FIRST AID (BEFORE PARALYSIS)
Mouth to mouth respiration, ensuring the patient does not turn a bluish colour. Attention must be paid to the cleaning of his airway of vomitus, tongue obstruction, dentures, etc. If an artificial airway is available, this should be inserted - but it is not essential. Artificial respiration may have to be continued for hours, until the patient reaches a hospital.
If delay has occurred, then external cardiac massage may also be required.
Reassure the patient, who can hear but not communicate, that he will be all right and that you understand his condition.
Enlist medical aid, but never leave him unattended to obtain this.

PREVENTION
Avoid contact with the octopus and be suspicious of apparently empty shells.
Requests by scientific groups for collection of these specimens should be tempered with caution.
A public education on the dangers of this animal should be directed especially to children who are attracted by the bright colouration.

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