Israeli scientists have invented a cream to guard swimmers against jellyfish stings.

Every year an estimated 130 million people are stung by jellyfish, which can cause rashes, pain and, in the case of certain jellyfish, death.

The key ingredients of the new cream are chemicals based on a substance fish use to protect themselves against stings. The firm that has produced the cream, Nidaria Technology, say it could be used to protect swimmers all over the world.

There are over 300 species of jellyfish that swim in the world's oceans. They are most common in the warm waters of the Caribbean, Asia and the Mediterranean.

Clumsy jellies

Jellyfish have in many respects remained remarkably simple organisms in more than 700 million years of evolution. They lack muscles, bones and the ability to hear and see, but their complex stinging mechanism make them fearsome ocean predators.

Even though jellyfish tend to avoid potential collisions, they are poor swimmers and sometimes can't avoid bumping into unlucky bathers.

A chemical in the skin of humans and other creatures triggers stinging cells located on the jellyfish's tentacles. The stinging cells contain poison-laden barbs called "tubules" held under extremely high pressure. When stinging cells sense a nearby creature they release approximately one million tubules that bury themselves in the skin

This all takes place in a few milliseconds - the speed of a bullet from a gun - making it one of the fastest cellular processes in nature.

Fish find

To find a way to prevent the stinging process jellyfish expert Dr Amit Lotan, and his molecular scientist wife Tamar, looked to the Clownfish. Clownfish live happily amongst the tentacles of poisonous stinging sea anemones, a relative of the jellyfish, thanks to a protective layer of mucous.

When the researchers wiped the mucous layer off and returned the fish to the anemones, they were stung straight away. The active component in this mucous forms the basis of the new cream which can be applied before swimming.

The component inhibits stinging cells from firing by interfering with several stages of their biochemical pathway, from the sensing mechanism through to reducing the pressure in the cells.

With funding from the Israeli government, the Lotans set up the company Nidaria Technology to develop and market their find.

Dr Amit Lotan told BBC News Online: "For me it's a type of revolutionary product, similar to when insect repellent was invented.

"Most creams give relief after someone is stung, but this is the first that actually prevents the sting in the first place."

Keep out of the water

Nidaria is now negotiating with sunscreen manufacturers around the world to manufacture their products jointly in a one-stop beach cream.

Nidaria say that their product is effective against at least 10 of the most common jellyfish but they have yet to try it out against highly dangerous speicies. These include the Australian box jellyfish, which has toxin more potent than cobra venom, killing a person in less than five minutes.

Apart from this new cream, the only ways to prevent being stung by a jellyfish is for swimmers to cover themselves from head to toe in nylon - the material used to make stockings - or to stay out of the water.