Boy infected by common octopus
The common octopus is not the placid creature we have been led to believe, warn experts, who report an unprecedented case of an octopus inflicting an infected bite on a child.
The bite, which did not heal and had to be removed, occurred while the nine-year-old boy was snorkelling with his uncle in Croatia.
He apparently provoked the normally peaceful Octopus vulgaris, which squirted its ink and bit him on the arm before swimming away.
The bite did not hurt or bleed at the time, but two days later a small red inflamed wound developed, with a haemorrhagic nodus in the centre.
A month later it had still not healed or responded to topical treatments, developing a black necrotic, ulcerous centre surrounded by redness and swelling.
Eight weeks after the incident the tissue was excised, with microscopic evaluation showing ulceration and extensive necrosis (dead infected tissue) of the upper tissue.
Bacterial cultures revealed infection with the gram-negative Pseudomonas oryzihabitans – claimed to be the first reported case of such an infection arising from an Octopus vulgaris, or common octopus.
Unlike its poisonous blue-ringed cousin Hapalochlaena maculosa - bites from which can be fatal – bites from the common octopus are extremely rare and wounds normally heal rapidly.
Writing this week in the Archives of Dermatology, the German authors of the report urged doctors to be vigilant for bacterial infections when treating skin lesions from marine animals.
“Marine animals may act as reservoirs and vectors for pathogens that are potentially to humans. Every wound that occurs in the marine environment can be affected,” said the authors, from the Technical University Munich.
They described the Octopus Vulgaris as “an intelligent peaceful marine animal and normally a loner”.
Despite having a small, parrot-like beak, its primary defences were either to hide in plain view by changing its colours, or to squirt ink at an attacker and swim away.
The majority of injuries from marine animals in Australia are caused by jellyfish, or spikes or barbs from other animals, with octopus bites “very rare”, according to a 2002 report from Melbourne.
The octopus in question could not be reached for comment.
Archives of Dermatology 2011
Wilderness & Environmental Medicine 2002; 13: 106-12.