Bathers’ scourge: a guide to jellyfish stings

With over 200 types that have been documented, 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.

Jellyfish, with the most popular in Malta being the mauve stinger, 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.

Jellyfish sting symptoms

A jellyfish sting causes an immediate painful inflammatory reaction to a toxin that the jellyfish injects into one's skin. The local reaction consists of swelling, redness, pain, itch and sometimes, oozing and crusting from secondary bacterial infection.

Unfortunately, a sting from a mauve stinger causes nasty reactions.

Besides the painful inflammatory reaction, which usually lasts from one to two weeks, one may end up with long lasting scarring and pigmentary discolouration. Jellyfish stings involving the eyes are likely to cause corneal scarring and blindness. Rarely, a jellyfish sting may cause a severe life-threatening generalised allergic reaction.

In people who are hypersensitive, the inflammatory reaction is more severe and tends to last longer. The solution is immediate treatment.

Also, sunburnt skin is more likely to result in long lasting pigmentary discolouration following jellyfish stings.

Treating the sting

A jellyfish sting should be rinsed immediately with seawater for five to 10 minutes and gently scraped with a linear edged-object such as a credit card, in order to disperse unexploded sting cells.

This should ideally be followed by application of vinegar or alcohol to stop sting cells from releasing their toxin.

Further medical treatment includes application a potent steroid cream, antihistamine pills, steroid pills if severe, and antibiotics if secondary bacterial infection, namely cellulitis, is suspected.

Steroid pills and antibiotics require a doctor's prescription. Medical treatment should be sought if the person stung has difficulty breathing, difficulty swallowing or chest pain or has been stung in the mouth and if the sting happened to someone who is very young or old.

Urinating on a sting: an old wives' tale?

It is not the first we have heard that urinating on the sting may relieve the pain of a jellyfish sting. However, several scientific researches insist urinating on a jellyfish sting might actually make the stinging worse... and not to forgetting the awkward situation if you're on a crowded beach.

"I am not aware of any evidence that urine helps," dermatologist Lawrence Scerri adds. "But any alcohol including vodka could be helpful."

Dr Lawrence Scerri warns:

• Avoid rubbing the area
• Do not apply fresh water
• Do not apply hot water
• Do not apply icepacks

All these actions are likely to trigger off unexploded sting cells and hence inflict more damage.

What about avoiding the sting in the first place?

While there are a number of creams that claim to protect against jellyfish, these might not always work. On the other hand, smothering oneself with something super-greasy like lard effectively minimises contact with jellyfish. Downside: of course, this is not practical.

"But, it would be a good idea to check the weather forecast for wind direction before setting off to the beach," Dr Scerri suggests.

The concentration of jellyfish in our waters varies from year to year depending on prevalent currents and alterations in the ecosystem such as fluctuations in predator and host ratios due to over fishing, illegal fishing and pollution.

Since jellyfish do not swim but float and drift with currents, they are more likely to be found in beaches where the wind is blowing inwards.

Facts about the brainless creature

• Jellyfish do not have a brain or central nervous system
• Some jellyfish are bigger than a human and others are as small as a pinhead
• In some countries people eat jellyfish
• Jellyfish first appeared about 650 million years ago and are found in every ocean, from the surface to the deep sea. Some are also found in fresh water
• Jellyfish are mainly made up of water and protein
• A group of jellyfish is called a 'smack', though more commonly used are 'bloom' or 'swarm'
• Box jellyfish venom is the most deadly in the animal kingdom and has caused at least 5,568 recorded deaths since 1954. Each tentacle has about 500,000 sindasites which are harpoon-shaped needles that inject venom into the victim
• Even a lifeless jellyfish has the capability to sting.