Aquatic Antagonists: Jellyfish Stings
Jellies, more commonly known as jellyfish, are a common cause of stings in oceans throughout the world. Most stings result in immediate painful skin reactions that can be treated with hot water immersion and careful removal of adherent tentacles. Rarely, certain jellyfish species can cause life-threatening systemic reactions that must be treated promptly and monitored in the acute care setting. Wearing a full-body stinger suit or applying a sting-inhibiting lotion are common strategies that may reduce the risk for jellyfish injuries. Avoidance of waters during jellyfish season is prudent in regions that harbor more dangerous species of jellyfish, particularly along the Australian and Indo-Pacific coastlines.
Practice Points
- Jellyfish stings occur an estimated 150 million times annually worldwide, with numbers expected to rise due to climate change.
- Most stings result in painful self-limited cutaneous symptoms that resolve spontaneously. Box jellyfish (Cubozoa) stings carry a greater risk for causing severe systemic reactions.
- Treatment of skin reactions includes removal of tentacles and hot water immersion. Vinegar dousing for at least 30 seconds is recommended for box jellyfish stings. Supportive care and monitoring for cardiovascular collapse are key. The role of antivenin is uncertain.
In the setting of anaphylaxis, patients should receive epinephrine and be transported to a hospital with appropriate hemodynamic monitoring and supportive care. If the species of jellyfish has been identified, species-specific antivenin also may be available in certain regions (eg, C fleckeri antivenin manufactured in Australia), but it is unclear if it improves outcomes when compared with supportive care alone.6,16
Conclusion
Following jellyfish stings, most skin lesions will spontaneously resolve. Patients likely will present days to weeks following the inciting event with mild cutaneous symptoms that are amenable to topical corticosteroids. Recurrent dermatitis following a jellyfish sting is uncommon and is thought to be due to an immunologic mechanism consistent with type IV hypersensitivity reactions. Patients may require multiple courses of treatment before complete resolution.20
Patient education regarding marine envenomation and mechanical barriers such as wetsuits or stinger suits can reduce the risk for injury from jellyfish stings. Sting-inhibiting lotions also are commercially available, though more research is needed.21 Many beaches that are known to harbor the dangerous box jellyfish provide stinger nets to direct travelers to safer waters. Complete avoidance during jellyfish season is recommended in highly endemic areas.1
