http://www.iht.com/articles/2009/01/07/asia/devils.php
'Demoralizing' setback in fight to save Tasmanian devil By Meraiah Foley Wednesday, January 7, 2009 SYDNEY: Cedric the Tasmanian devil was supposed to be the savior of his species. Researchers believed the 3-year-old male marsupial was immune to a devastating facial cancer that has pushed the species to the brink of extinction. But last month, Cedric's handlers discovered two small tumors on his cheek - a major setback in the search for a vaccine. Now, some scientists want to build a fence on Tasmania, the Australian southern island, to protect the last disease-free devils from the infectious cancer that has killed more than half the wild devil population since it was discovered in 1996. Devil facial tumor disease - which is spread when the animals bite each other - causes swollen, ulcerating wounds around the eyes and mouth. Once infected, wild devils eventually die of starvation when the tumors grow so large that they can no longer eat or drink. Researchers at the University of Tasmania warn the cancer is spreading so rapidly that there may be no disease-free devils left in the wild within 5 years, and that the species could be extinct entirely within 20 years. Wild devils live only in Tasmania. Multiple conservation efforts are under way across Australia to quarantine healthy devils in zoos and breeding programs while scientists hunt for a cure. A team of cancer specialists led by Greg Woods, an immunologist at the Menzies Research Institute in Hobart, Tasmania's capital, thought they were on the right track when they discovered Cedric. Woods inoculated Cedric and his half-brother Clinky with irradiated - or dead - tumor cells, and then injected them both with live tumor cells to see if the dead cells would act as a vaccine. Cedric produced antibodies in response to the live cells and developed no tumors; Clinky succumbed to the cancer. In July last year, Woods injected Cedric with a slightly different strain of the cancer to see if he had a natural immunity. At first, the results looked promising. For five months, Cedric showed no sign of illness. Local newspapers called him "the last great hope" of his species, and plans were floated to put Cedric to stud to spread his disease-resistant genes through the wild devil population. These hopes were dashed in December, when Cedric developed two small tumors at the site of his last injection. Woods's team members removed the tumors and are now analyzing them to determine why Cedric fought off the disease the first time but developed it at the second exposure. It is possible that Cedric may have simply needed a booster shot, Woods said. Or perhaps Cedric has some immunity to the first strain of the disease, but not the second. "It was quite demoralizing," Woods said by telephone. "It means we're going to have to take a couple steps back or to the side to try and look to see what happened here and modify the immunization protocol." In the absence of a vaccine, scientists are calling for radical measures to protect the devils from extinction. Quarantine is one option. Around 170 healthy devils have been placed in breeding programs across Australia. The intent is to keep a large enough pool of the animals alive to avert extinction. Researchers at the University of Tasmania's Devil Facial Tumor Disease Program are also looking at whether it would be possible to build a fence that would keep infected devils in the northern and eastern regions of Tasmania from spreading into the west, which is still untouched by the disease. The idea is not without precedent. In the early 1900s, Australia built a 3,200-kilometer-long, or 2,000-mile-long, fence across the outback to stop rabbits from encroaching on agricultural land in the west. The fence slowed the spread of the rabbits for about a decade, but was ultimately unsuccessful. Another idea being explored by the Save the Tasmanian Devil Program, a collaboration of scientists and conservationists, involves putting enclosures around smaller communities of healthy devils in the wild. But scientists still have much to learn about the animals' feeding and nesting habits before that proposal can have any chance of success, according to the program's manager, Andrew Sharman. "There is no single, simple solution to what research has shown is an evolving disease," Sharman said in a statement.
