Blue-ringed octopus: a beauty to look at but don’t touch
Blue-Ringed octopuses are very small organisms, belonging to the genus Hapalochlaena (Cephalopoda - Octopodidae). They are the size of a golf ball but its venom is powerful enough to kill an adult human in minutes. The bite might be painless, but this octopus secrets a neuromuscular paralyzing venom.
The venom is not injected but is contained in the octopus’s saliva, which comes from two glands each as big as its brain. The venom contains some maculotoxin, a substance more violent than any found on land animals. This substance blocks the nerve conduction and causes neuromuscular paralysis, followed by death. The venom also contains tetrodotoxin, which blocks sodium channels and causes motor paralysis and occasionally respiratory failure. Though with fixed dilated pupils, the senses of the victims are often intact, they are aware but unable to respond.
There’s no known antidote, but the victim might be saved if artificial respiration starts before marked cyanosis and hypotension develops. The only treatment is hours of heart massage and artificial respiration until the toxin has worked its way out of your system.
Some symptoms that may be experienced when the toxin enters the system are: onset of nausea, hazy vision (within seconds you are blind), loss of sense of touch, speech and the ability to swallow.
Although the painless bite can kill an adult, injuries have only occurred when an octopus has been picked out of its pool and provoked or stepped on. So be careful in the Australian beaches, and, please, don’t touch this cute octopus.
Blue-Ringed Octopus Bite First Aid:
1.- This bite is considered a medical emergency so do not wait for symptoms to develop; quickly get the person bitten out of the water and, if possible, call the emergency number and consider transport to the nearest hospital.
2.- Use the pressure immobilization technique: wrap the limb with an elastic bandage. It should be tight, but the fingers and toes should remain pink so that the circulation is not cut off. The extremity should also be immobilized with a splint or stick of some sort. The elastic bandage should be removed for 90 seconds every 10 minutes and then reapplied for the first 4 to 6 hours (hopefully medical care can be received within this time period). If 30 minutes or more has passed since the blue-octopus bite, the pressure immobilization technique is not likely to be helpful.
3.- If the victim is having difficulty breathing, assist with mouth-to-mouth ventilation.
When a victim is kept alive the poison gradually wears off after 24h, apparently leaving no side effects.
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Photo credit: ©Bjørn Christian Tørrissen | Locality: Sidney, Australia