Jellyfish stings, rashes and bites

Sometimes a swim at one of our beaches can put you at risk of rashes, stings and bites. Jellyfish are the most common cause of these.

Some beaches have more jellyfish than others. The risk at a beach can vary from day to day, but tends to increase when seawater warms up in summer.

The best way to keep yourself safe is to visit Safeswim before you go in the water and check it is ok. Safeswim provides up-to-date information on:

  • water quality
  • sun protection
  • beach hazards
  • dangerous animal sightings, and
  • tidal conditions

Most types of jellyfish in New Zealand’s waters are harmless. In the Auckland region the types most known to cause issues are:

  • Bluebottle jellyfish

These produce a nasty sting and people should stay out of the water if these jellyfish are known to be present.

  • Microscopic jellyfish

These jellyfish are very small and transparent. They can get trapped in your swimwear or hair and sometimes will go unnoticed until you get out of the water. As a swimmer gets out of the sea, water drains from the swimwear and traps the jellyfish between the fabric and the skin, causing the stinging cells to release their toxin.

If you are stung by a jellyfish you may experience:

  • a burning, stinging sensation on your skin
  • a tingling or numbness where the sting occurred
  • the skin in the area where the jellyfish stung turning red or purple

If you are stung by microscopic jellyfish the rash, called sea bather’s eruption, may not appear until well after you have left the sea. The rash often becomes itchy and sore, and can vary from mild to severe, lasting up to a week.

Following a jellyfish sting children and people with allergies may get more severe reactions. They can become unwell for several days.

More severe symptoms of a jellyfish sting can include:

  • nausea
  • dizziness
  • vomiting
  • difficulty breathing

If you are concerned call Healthline on 0800 611 116 or see your doctor or practice nurse.

For up-to-date information on self-care following a jellyfish sting visit the Health New Zealand (NZ) - Te Whatu Ora website. 


Self-care for jellyfish stings

If a jellyfish stings you or a family member, get out of the water and follow these steps to treat the sting area.

  1. Flush the stung area with seawater (or fresh water, if sea water is unavailable) to remove the tentacles.
  2. If tentacles are still attached use a dry towel to remove them. Wear gloves if you have some.
  3. Immerse the stung area in heated tap water for 15 to 20 minutes. Have it as hot as the person can bear without causing skin burns (and no more than 45° C). A shower can be used for stings to the torso. You can repeat the immersion for up to 2 hours after the injury, but be sure to limit the hot water immersion to 15 to 20 minutes at a time (with breaks between to allow cooling of the skin).
  4. Take pain relief following hot water immersion

Do not apply vinegar or methylated spirits as they can make the sting more painful. Vinegar is only effective for Box jellyfish (found in Australia).

If you need help the National Poisons Centre is available 24 hours a day on 0800 764 766. They can provide advice on first aid and treatment of stings.

If you are concerned call Healthline on 0800 611 116 or see your doctor or practice nurse.


When to contact your doctor

Call your doctor if you have been stung and have:

  • increasing numbness or difficulty breathing
  • signs of poisoning: abdominal pain, muscle cramps, nausea, vomiting
  • signs of infection later: increasing pain, redness, swelling, red streaks leading away from the sting, heat, discharge of pus, fever or chills
  • pain that is not controlled by following the self-care instructions
  • any new or worsening symptoms
  • A contaminated wound (a tetanus injection may be required).

You should also get medical help if you have a severe allergic reaction (an anaphylaxis). It is rare for a patient to have an anaphylaxis to jellyfish, even if they are stung on the face or neck.

National Public Health Service (NPHS) - Northern Region supports regional and district councils with messages regarding health and safety on beaches and when swimming.

NPHS - Northern Region is a partner of Safeswim, which is updated regularly and provides advice on:

  • water quality
  • sun protection
  • beach hazards
  • dangerous animal sightings, and
  • tidal conditions


There are specific requirements for notifiable diseases in the Auckland region.

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Last updated 25.3.2024

For health advice call Healthline for free anytime on 0800 611 116
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