Australia: Chlamydia wreaking havoc on Koalas, climate change worsening situation

Chlamydia, a sexually transmitted bacteria is wreaking havoc on Australia's koala population. It is posing a threat that wildlife experts say could wipe out the iconic marsupial across much of the country. Chlamydia infects more than 100 million people worldwide each year and can cause infertility in humans if left untreated. Uncontrolled chlamydia can cause blindness and painful cysts in the reproductive tract of koalas, leading to infertility or even death.

Worse, antibiotics used to treat the disease can destroy the delicate gut flora required by koalas to consume their staple diet of eucalyptus leaves, causing some to starve to death even after being cured. In addition, the disease has the potential to spread quickly. CNN reported, according to Mark Krockenberger, a professor of veterinary pathology at the University of Sydney, there was a very, very low chlamydial prevalence – about 10% – in the koala population in Gunnedah, a rural town in northeast New South Wales, in 2008.

By 2015, that figure had risen to as much as 60%. Krockenberger estimates that about 85% of the koala population is now infected with the disease. When you think about it, that's no longer a viable population due to infertility. Almost every female infected with Chlamydia becomes infertile within a year, maybe two years... Even if they do survive, they are not reproducing, Krockenberger added, CNN reported.

Experts say situations like the one in Gunnedah are playing out across Australia's koala populations, threatening populations that are already vulnerable to worsening bushfires and habitat loss due to deforestation. To protect the animals, scientists are currently testing vaccines against Chlamydia. The grey, fluffy-eared marsupial, which eats eucalyptus leaves and carries its young in its pouch, is found only in Australia and is frequently depicted in cultural representations of the country.

CNN reported citing the Australian government report when marsupials are subjected to unusually stressful environmental conditions such as hot weather, drought, habitat loss, and fragmentation, chlamydia spreads more quickly through their population. Experts say they've seen similar rapid outbreaks of disease in the wild. According to CNN, Krockenberger claims that a series of heatwaves and droughts in 2009 and 2010 preceded a doubling of chlamydia cases in his Gunnedah sample population.

Koala is classified as "vulnerable" on IUCN Red List

Koalas, on the other hand, face a number of threats to their survival. Aside from disease, marsupials face habitat loss, are frequently attacked by wild dogs, and are hit by cars. The koala is classified as "vulnerable" on the International Union for the Conservation of Nature's (IUCN) Red List of threatened species. The IUCN estimates that there are between 1,00,000 and 5,00,000 koalas in the wild, but the Australian Koala Foundation estimates that the figure is closer to 58,000. The country's koala population suffered significant losses during the 2019 bushfires, which destroyed over 12 million acres (48,000 square kilometres) of land in New South Wales alone.

Australia has become more vulnerable to devastating bushfires, such as those seen in 2019, as well as drought and heatwaves, as a result of climate change. It also makes koalas more vulnerable to disease. According to the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia has already warmed by about 1.44 degrees Celsius on average since 1910.

(With inputs from agencies)

Image: AP