Irukandjis and box jellyfish are more prevalent in the tropics, but have been reported well outside the tropics on occasion. Irukandji syndrome is confirmed in such unlikely and disparate localities as Hawaii, Florida, the Caribbean, North Wales (in the U.K.), Cape Town, Sydney, Melbourne, Perth, India, Japan, and throughout the tropical Indo-Pacific region. Without doubt, Irukandji jellyfish, and therefore Irukandji syndrome, can occur anywhere in the tropical and temperate seas of the world.

There is growing evidence that Irukandji stings are just as common overseas as in tropical Australia, if not more so, but have been recognised longer and more well studied in Australia, thus skewing the records.

Regions such as Africa and South America most certainly must have incidents of Irukandji syndrome and fatal box jellyfish stinging; however, lack of recognition or lack of reporting may account for the apparent lack of stings in these regions.

The map above is not comprehensive, but is offered as a general pattern.