Lethal Irukandji Syndrome in Queensland, Australia

Editor’s Note

In a 1999 article that appeared in Australian Family Physician, Fenner and Carne noted an unusually high number of Irukandji victims who had required admission to intensive care facilities.1 However, even in their report of events occurring in Australia between 1996 and 1999, no deaths had been noted. This recent newspaper account serves as a warning that Irukandji syndrome can be fatal, and that its incidence appears to be increasing. Why? And what is Irukandji syndrome anyway?

The stings from the tentacles of the Carukia barnesi jellyfish can result in severe sympathetic overdrive causing hypertension (responsive to a-blockers such as phentolamine), tachyarrythmias, profuse sweating, and shaking. This syndrome ultimately leads to pulmonary edema from hypokinetic cardiac failure that requires inotropic support and monitoring.

The recent trends, which are recounted in the following article from the Science section of The New York Times,2 should alert travel medicine providers and their patients to the dangers associated even with apparently mild stings by small box jellyfish, such as Carukia. At the very least, swimmers and divers in endemic geographic regions must be aware of the possibility of jellyfish exposure and how to inactivate their stinging capsules with vinegar. Thirty minutes after an untoward sting they could be well on the path to cardiogenic shock. Specific antivenom is available in places like Cairns, Queensland, where its administration, coupled with appropriate life support measures, may be critical to survival. —Frank J. Bia, MD, MPH, Professor of Medicine and Laboratory Medicine; Co-Director, Tropical Medicine and International Travelers' Clinic, Yale University School of Medicine.


1. Fenner P, Carney I. The Irukandji syndrome. A devastating syndrome caused by a north Australian jellyfish. Aust Fam Physician. 1999;11:1131-1137.

2. Pohl O. New jellyfish problem means jellyfish are not the only problem. New York Times. May 21, 2002:F3.