Auckland Regional Public Health Service says microscopic jellyfish are at the root of rashes found on Auckland beach bathers this summer.
Warm weather and onshore winds can bring jellyfish larvae into beaches during the warmer months, and they can appear at any Hauraki Gulf beach at any time.
Medical Officer of Health, Dr Simon Baker, says the majority of stings at Auckland beaches in recent years have been caused by Hydromedusae jellyfish – the larval form of larger jellyfish – rather than sea lice.
“Sea lice are fish parasites and do not bite humans. It is almost certain that the rash under swimwear is caused by hundreds, even thousands, of small jellyfish stings.
“When a bather drains their swimsuit, the jellyfish are trapped tightly against the skin, and their stinging cells release the toxin. If you think you’ve been stung, make sure you use the shower at the beach to wash off the jellyfish, rather than sit around in your wet togs.
"A saltwater shower works best, but freshwater is almost as good. Then, change out of your togs as soon as possible.”
Dr Baker also suggests giving your togs a good wash when you get home if you suspect you have been stung.
“Jellyfish can still sting even after they are dead. It is possible to get stung weeks after initial contact, if your togs haven’t been washed properly.”
Auckland Regional Public Health Service recommends that swimmers wear lycra togs instead of baggy clothing, as baggy clothing gives the jellyfish more material to grasp onto.
Children appear to be a common target for jellyfish, possibly due to their softer skin. Jellyfish stings can cause a mild itchy, but painful, rash that can last a week. Calamine lotion, antihistamines and mild steroid creams such as 0.5 per cent or 1 per cent hydrocortisone may be helpful but if symptoms persist or worsen, please visit your doctor.
If you are visiting the beach on a nice summer's day, be prepared and take a change of clothes. This may prevent stinging, or further discomfort and pain in the event of a jellyfish sting.
For more information on jellyfish stings, please visit the Auckland Regional Public Health Service website.