[escudo]

According to a Discovery Channel show 2005/07/28, they are found in warm waters WORLDWIDE, with a local summer-ish stinging season. The stinging season is reported to be increasing in duration year by year.

The map in particular showed coasts of Australia, Great Barrier Reef, Africa, Florida (and other southern parts of US), and Indian Ocean if I remember correctly. There were other areas marked as well, but I can't be as specific. I would assume in the US this would include Gulf of Mexico and Gulf of California as well (which is where I've done most of my diving, and been stung with no ill effect many times by small-jelly swarms...obviously not Irukanji...I now see this risk in an entirely new light).

There is NO ANTIVENIN, and work is extremely limited on producing one as the researchers apparently have numerous species to contend with, and each species has a unique antivenin requirement. One researcher said there would be no point to producing an antivenin at this point in time because more isolation work was required. The current treatment is symptomatic.

The show indicated treatment with morphine (extremely high dangerous doses) for pain, and antihistamines for blood pressure reduction. For the muscle spasms, they didn't mention any pharmacological treatment, but I understand Valium is often used in OTHER instances of animal envenomation along with morphine. It may be that at the doses of morphine required here, that co-administration of Valium might be too dangerous? In one case noted on the show, they also applied an external neutralizing wash but didn't say whether it actually did any good or not against this particular sting.

They also indicated that some researchers suspect that many cases previously considered drowning at sea might be attributable to this creature.

Based on these new data, I'd think any diver feeling a sharp sting, and unable to absolutely positively determine it is from a benign species, had best head immediately to the dive boat or beach. The onset of crippling symptoms is measured in minutes.

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After reading some related posts at another site, I decided to add a few more thoughts to clarify some issues.

The apparently multiple species of this animal could account for different sizes, number/length of tentacles, symptom severity, etc. reported. One post suggested symptoms in cooler waters didn't seem as severe. This may be due to a different species of Irukanji. One post said he saw Irukanji in waters as cold as 20degC. I think it's reasonable to expect there might be significant differences between jellys that prefer 33degC v. 20degC.

The number of fatal encounters has increased dramatically over the past two years. This (in my opinion) may be due to wider range of warm waters/warmer waters, changes in currents, and/or increases in recreational ocean diving/swimming.

It makes sense that in planning a dive trip now, that the onboard medical capabilities of the dive master and boat be fully understood before committing. Many dives can be 10 or more hours away from medical help in undeveloped locations, and the ability to deal with envenomation as well as trauma seems to be increasingly significant.