Bluebottle (Physalia spp.)

The Portuguese man-o-war or bluebottle, is well known throughout Australian waters (and both the pacific and Atlantic oceans) for causing painful stings. No fatalities have been confirmed in Australia. The bluebottle is not a jellyfish sensu stricto, but a colony of animals closely related to jellyfish. The float measures 2-15 cm. The main or fishing tentacle may be up to 10m long and is responsible for most of the stings. The larger Atlantic specimens probably represent more of a threat to human life. The venom contains lethal and haemolytic components and has been shown to produce nerve conduction disturbances, flaccid paralysis and smooth muscle contraction in experimental animals. In human envenomation, pain is the most prominent feature, along with localized skin lesions with a "string of beads" appearance; discrete weals surrounded by erythema. Systemic symptoms are uncommon but may include headache, nausea and vomiting, abdominal pain and occasionally collapse. First aid consists of removal of the tentacles, preferably with forceps. Vinegar is not recommended. Analgesia may be required, although most stings respond to ice packs and/or topical anaesthetic agents.