Jellyfish incident

  • Safety Flash
  • Published on 29 July 2005
  • Generated on 25 February 2026
  • IMCA SF 08/05
  • 2 minute read

A Member has reported an incident that occurred during surface diving operations offshore of Western Australia, whereby a diver was apparently stung by a Carukia barnesi jellyfish, which led the diver to develop Irukandji syndrome.

What is Irukandji syndrome?

  • Irukandji syndrome is a group of delayed (between 10 and 40 minutes) severe systemic symptoms occurring after an initial mild skin sting by small carybdeid (box) jellyfish including Carukia barnesi, known colloquially as the ‘Irukandji’. The syndrome is well known in tropical Australian waters.

  • About 5-45 (usually 30) minutes after being stung, the person starts to develop ‘Irukandji syndrome’ – a set of symptoms that often include severe lower back pain, muscle cramps, vomiting, restlessness and anxiety. 

  • In rare cases, the victim can suffer pulmonary oedema (fluid on the lungs), hypertension or toxic heart failure that could be fatal if not treated.

What were the causes?

The incident was attributed to the following basic causes;

  • The diver was stung and envenomated by Irukandji jellyfish.

  • Loose overalls had allowed jellyfish to enter at the back of the neck during surface swimming – the Irukandji jellyfish is typically between 1-2.5 cm across the body and is therefore able to enter through small areas.

Actions

Our Member has recommended the following actions for the geographical area concerned:

  • Correct PPE should be used for surface swimming, air diving and saturation diving.

  • Stinger suits should be worn under all coveralls whilst diving unless wearing a wetsuit.

  • Diving hoods should be used at all times whilst surface swimming.

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