Researchers have announced a groundbreaking vaccine designed to protect koalas from chlamydia, a disease that significantly contributes to their mortality rates. This vaccine, described as a world-first, is expected to make a considerable impact on efforts to combat this deadly illness.
Developed over a span of more than ten years at the University of the Sunshine Coast (UniSC) in Australia, the single-dose vaccine does not require a booster shot. The aim is to mitigate the rapid and devastating spread of chlamydia among koala populations.
Peter Timms, a microbiology professor who led the research, remarked that some koala colonies face imminent extinction, especially in regions like South East Queensland and New South Wales where infection rates can soar to around 50 percent or even higher in certain cases.
Chlamydia can lead to severe issues for koalas, including blindness, which can impede their ability to find food, eventually causing starvation. The disease also causes infertility and can inflame the bladder, leading to bleeding, per Koala Conservation Australia.
This disease is transmitted in several ways, such as through mating or infected discharges, and even at birth. Joeys, for instance, may contract chlamydia by consuming “pap,” a substance produced by their infected mothers that resembles feces.
While antibiotics have been used for treatment, they are not always effective and don’t prevent future infections. Furthermore, they can cause gastrointestinal side effects that might impair the koalas’ ability to digest eucalyptus leaves, their primary food source. In advanced cases, euthanasia might be necessary.
This is why the introduction of this vaccine is generating optimism among scientists.
Sam Phillips, a senior researcher at UniSC, mentioned that the vaccine has undergone testing with both wild and captive koalas. It works by targeting Chlamydia pecorum’s major outer membrane protein (MOMP) and provides multiple levels of protection: it reduces the risk of infection, prevents the disease from worsening, and can, in some situations, reverse existing symptoms.
A study led by Phillips last year reported that the vaccine not only lessened the signs of chlamydia during koalas’ breeding periods but also reduced deaths from the disease by 64%.
The Australian Pesticides and Veterinary Medicines Authority (APVMA) has officially approved the vaccine for production and distribution. They’ve issued a permit that allows for its use in koalas, which is set to last until June 2027.
