In reply: While overcoagulation causing intracerebral haemorrhage could have caused the death of the patient we described,1 he was normotensive until developing signs and symptoms of Irukandji syndrome some 20 minutes after being stung. The Irukandji syndrome is, and always has been, a clinical diagnosis only. Biochemical and pathological test results become abnormal later, but are not diagnostic — actual cause and effect have been described only once, with the experiment unlikely to be repeated!2

Nematocyst studies, while established for Chironex fleckeri,3,4 have never identified species associated with Irukandji syndrome, except Carukia barnesi, which appears to occur in the Cairns area only. Other species probably cause the more severe syndrome seen in the Whitsundays and on the Great Barrier Reef, where these deaths occurred.5 One of us (P J F) is possibly the only person to have captured specimens likely responsible for causing Irukandji syndrome from the Whitsundays, and the species remain unidentified, as they are a new species and not described to date. Also, when the moribund patient was admitted, no obvious sting site was visible, and a negative skin scraping would not rule out a jellyfish sting.

Phentolamine has previously proved effective for relieving distressing autonomic symptoms,6 and not just for cardiovascular complications, although it appeared ineffective at the lower doses used in our patient. However, nothing appears to prevent toxic cardiac dilatation occasionally occurring later in the syndrome.7 Further research is currently under way.

Antivenom development may prevent some (possibly all) major symptoms of Irukandji syndrome. However, production is impossible until sufficient specimens of all species (some six to 10) causing the syndrome are caught and their venom assessed. Such advances are many years away and may never be achieved with current poor levels of funding.

Cardiac markers for jellyfish envenomation have previously been identified.5,8 Since 1999 troponin level has replaced creatine kinase isoenzyme (CK-MB) level, and both are invariably raised in patients stung by the Whitsunday jellyfish. Thus, the words "cardiac markers" should have been used in the article and for not doing so I apologise.

Despite C. barnesi stings being common at north Cairns beaches, it has taken six years of dragging the beaches, with nets to catch jellyfish of this species. The thought of trying to catch a 12 mm jellyfish that makes erratic and irregular appearances in several hundred square kilometres of ocean around the Whitsunday Islands is totally daunting, but the possibility is being assessed. Such a venture will depend on funding becoming available.

Other stings were reported in the area at the time of our patient's death and are well known at the resorts where people who have been stung in surrounding areas are taken for treatment. However, stings remain erratic; they have no predictable patterns of appearance, and unfortunately prophecy is currently impossible.