This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
Tasmanian devils (Sarcophilus harrisii) just can’t catch a break. The infamous Australian carnivores have already been nearly wiped out by an incurable communicable cancer called devil facial tumor disease (DFTD), which first appeared in 1996 and has since killed as much as 90 percent of the entire species. As if that weren’t bad enough—and it’s pretty awful—now we have word that another disease has appeared on the horizon.
This time around it’s a bacterial infection called leptospirosis, which is often fatal in both humans and wildlife if left untreated. Leptospirosis—caused by a genus of spiral-shaped bacteria called Leptospira—has been seen in Australia before but never in Tasmanian devils. Early symptoms of the infection (which vary by species of bacteria and host) include headaches and nausea. Later, much more severe symptoms can include bleeding in the lungs and meningitis. The infection can usually be knocked out by antibiotics, although it can leave behind permanent liver or kidney damage.
The presence of the bacteria in the marsupials was uncovered by Sarah Wynwood, a PhD student at the University of the Sunshine Coast in Queensland, who earlier this year developed the first new test to diagnose the bacteria in more than a century.
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A native of Tasmania, Wynwood recently conducted leptospirosis tests on her state’s iconic devils—for which she says she has “a soft spot”—to see if any factors besides DFTD may be contributing to their decline. She tested samples from 83 animals and, using multiple testing methodologies, found leptospirosis antibodies in 11 of them.
Not only did she find the bacteria, she discovered a new strain that had never before been observed.
Wynwood says the devil tissue samples came from a wide range of locations, so the bacteria did not appear to be limited to any specific region or location.
The discovery supports earlier theories that a co-infection could be weakening Tasmanian devils’ ability to fend off the deadly cancer. So far, however, there’s no obvious link between DFTD and the Leptospira pathogen, but Wynwood says that’s the focus of the next phase of her research.
Will this new bacterial research actually yield another possible avenue toward protecting Tasmanian devils before DFTD wipes them all out? It’s too early to say, but at this stage any hope or new research path is all we’ve got.
Photo by James Stewart. Used under Creative Commons license
Previously in Extinction Countdown: