Nav: Home

Last chlamydia-free koala population may safeguard future of species

July 02, 2019

DENVER/July 2, 2019 - The last, large, isolated, healthy chlamydia-free population of koalas in Australia may have been identified on Kangaroo Island, said Morris Animal Foundation-funded researchers at the University of Adelaide.

Chlamydia is a serious threat to the species, contributing to dramatic population declines, and the team hopes the Kangaroo Island koalas can provide a safeguard against further losses and even extinction. The team published their findings in the Nature journal Scientific Reports.

"This is a very important finding because chlamydial disease is so prevalent and efforts to fight it have so far been unsuccessful," said Dr. Natasha Speight, koala researcher and lecturer at the University of Adelaide's School of Animal and Veterinary Sciences. "These koalas could potentially be used as a disease-free breeding colony in the future."

Chlamydia pecorum is a bacterial infection of koalas that is mainly transmitted sexually, but also can be spread by close contact, including from mothers to joeys. It develops as conjunctivitis, which can lead to blindness, and urinary tract infections that can ascend to the kidneys and reproductive tract, causing infertility. Chlamydia is common in koalas and ultimately fatal.

"The impact of Chlamydia on populations of koalas in parts of Australia is devastating, with high levels of severe disease and death, and common infertility," says lead author Jessica Fabijan, from the University of Adelaide. "This last Chlamydia-free population holds significant importance as insurance for the future of the species. We may need our Kangaroo Island koalas to re-populate other declining populations."

The Morris Animal Foundation-funded study sought to determine the prevalence of C. pecorum in wild-ranging koalas. Based on previous evidence that found low or no infection rates, the study focused on wild koalas in the Mount Lofty Ranges, a mountain range just east of Adelaide, and Kangaroo Island (KI), Australia's third largest island, 70 miles southwest of Adelaide.

The team worked in conjunction with the South Australian Government Department for Environment and Water (DEW) and the University of the Sunshine Coast. They captured and released 75 koalas from the Mount Lofty Ranges and 170 koalas from KI. Veterinarians checked each koala and collected swab samples to test for C. pecorum DNA. Researchers also examined more than 13,000 historical veterinary records of KI koalas from over a 22-year period for accounts of the disease.

They found that nearly half of the Mount Lofty Ranges koalas were positive for C. pecorum DNA, but showed no signs of disease, except for three koalas. The koalas at KI, however, were all C. pecorum negative and no disease was observed. There were also no definitive records of the disease in the island's historical records. The team used the results in a statistical model that showed, with 95% confidence, that Kangaroo Island is C. pecorum-free.

"This could be the break we need to finally turn the tide on this infection and improve conservation efforts," said Dr. Janet Patterson-Kane, Morris Animal Foundation Chief Scientific Officer. "We're proud to support this work to save one of the world's most unique and beloved animals."

Morris Animal Foundation is one of the largest nonprofit animal health research organizations in the world, funding more than $126 million in studies across a broad range of species since 1948. The Foundation is one of the only organizations funding health research particularly for endangered and at-risk wildlife species, including the koala. The Foundation has funded numerous studies in koalas, including another devastating infection, koala retrovirus.

Chlamydia was first discovered in koalas in northern Australia in the 1970s. Populations there are declining, due to the disease and other threats, such as habitat destruction and road deaths. Koalas are classified as vulnerable by the International Union for Conservation of Nature's Red List of threatened species. Their populations in southern Australia are considered stable, thought to be partly due to a lower prevalence and severity of the disease.
About Morris Animal FoundationMorris Animal Foundation's mission is to bridge science and resources to advance the health of animals. Founded by a veterinarian in 1948, we fund and conduct critical health studies for the benefit of all animals. Learn more at

Morris Animal Foundation

Related Infection Articles:

Revealed: How E. coli knows how to cause the worst possible infection
The discovery could one day let doctors prevent the infection by allowing E. coli to pass harmlessly through the body.
UK study shows most patients with suspected urinary tract infection and treated with antibiotics actually lack evidence of this infection
New research presented at this week's European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) in Amsterdam, Netherlands (April 13-16, 2019) shows that only one third of patients that enter the emergency department with suspected urinary tract infection (UTI) actually have evidence of this infection, yet almost all are treated with antibiotics, unnecessarily driving the emergence of antimicrobial resistance.
Bacteria in urine doesn't always indicate infection
Doctors should think carefully before testing patients for a urinary tract infection (UTI) to avoid over-diagnosis and unnecessary antibiotic treatment, according to updated asymptomatic bacteriuria (ASB) guidelines released by the Infectious Diseases Society of America (IDSA) and published in Clinical Infectious Diseases.
Subsidies for infection control to healthcare institutions help reduce infection levels
Researchers compared three types of infection control subsidies and found that under a limited budget, a dollar-for-dollar matching subsidy, in which policymakers match hospital spending for infection control measures, was the most effective at reducing the number of hospital-acquired infections.
Dengue virus infection may cause severe outcomes following Zika virus infection during pregnancy
This study is the first to report a possible mechanism for the enhancement of Zika virus progression during pregnancy in an animal model.

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...