The stinging seas

时间:2019-03-07 08:09:03166网络整理admin

By Julia Hinde in Melbourne THE hunt is on for a thumbnail-sized jellyfish with a sting that is thought to be life-threatening to swimmers. No one has been able to catch the jellyfish Carukia barnesi in sufficient numbers for thorough scientific study, but over the next three months, scientists will attempt to net large quantities of them in the seas off northern Queensland, Australia. Researchers believe that stings from the small, transparent jellyfish can cause Irukandji syndrome, which can lead to severe hypertension, abnormal heartbeat and fluid build-up on the lungs. Such symptoms have been recorded throughout the tropical Pacific, and in some years, many hundreds of people in northern Queensland develop these symptoms in the summer. But studying the jellyfish has been almost impossible. “The problem is to catch them,” says Ken Winkel, director of the Venom Research Unit at Melbourne University. “Being thumbnail-sized and transparent, they are hard to spot.” Now a team of scientists from the University of California at Berkeley, Surf Life Saving Australia and Reef Biosearch in Port Douglas, Queensland, will spend the next three months in the waters off northern Queensland, including areas of the Great Barrier Reef, collecting samples. The goal is then to extract venom and show that the jellyfish do indeed cause Irukandji syndrome. Hopefully, it will also be possible to develop an antidote to the venom. Some of the best proof so far of the association between Carukia barnesi and Irukandji has come from the unorthodox tests by a Queensland doctor. In 1962, he deliberately let the jellyfish sting himself and his son. Both ended up in hospital with symptoms. Scientists are keen to find out if Carukia barnesi is dangerous at all stages of development. One of the puzzles about the jellyfish is why the intensity of symptoms varies so much in its victims. Some experience tremendous pain, nausea and vomiting; for others, a sting can result in heart failure. The scientists are keen to learn whether the range of reactions is due to stings from different species of the jellyfish, or is related to the site of the sting or individual reactions. “We think there may be several species of jellyfish causing this illness,” says Winkel, adding that last year a patient was admitted to a Victoria hospital, in the far south of Australia, with Irukandji-like symptoms. She had been swimming locally, but had not been to the tropical Pacific. “The jellyfish we think causes Irukandji has not been identified down here,” says Winkel, who suggests that the report from the Victoria hospital may point to a different jellyfish also being responsible for Irukandji. Or it might even indicate that Carukia barnesi is expanding its territory,