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Jellyfish Stings

Facts on Jellyfish Stings

  • Jellyfish are free-swimming, non-aggressive, gelatinous marine animals surrounded by tentacles.
  • These tentacles are covered with sacs (nematocysts) that are filled with poison (venom) that can cause a painful to sometimes life-threatening sting.
  • The marine animals included in this "family" are:
    • jellyfish,
    • box jellyfish (sea wasps),
    • Portuguese man-of-war,
    • hydroids,
    • anemones, and
    • fire coral.
  • Jellyfish are found throughout the world. But, the most deadly are found in the Indo-Pacific and Australian waters.
  • Jellyfish are usually found near the surface of the water during times of diminished light, floating in the water column, or after washing up on the beach.
  • Jellyfish stings are generally accidental - from swimming or wading into a jellyfish or carelessly handling them.
  • Some types of jellyfish have reproductive jelly gatherings 8 to 10 days after a full moon, thus there is an increase in the number of jellyfish found at that time.
  • There are over 200 types of jellyfish (that have been documented).

What Are Jellyfish Sting Symptoms?

  • Symptoms include an intense, stinging pain, itching, rash, and raised welts.
  • The progressive effects of a jellyfish sting may include nausea, vomiting, diarrhea, lymph node swelling, abdominal pain, numbness/tingling, and muscle spasms.
  • Severe reactions can cause difficulty breathing, coma, and death.
  • A sting from a box jellyfish or other venomous types of jellyfish can cause death in minutes.
Medically Reviewed by a Doctor on 10/17/2016

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With more than 10,000 species in the sea, jellyfish are responsible for the most common human envenomations.

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