Trials of the vaccine showed it reduced the likelihood of the herbivores developing chlamydia during breeding age and decreased deaths in wild populations by at least 65%.
Antibiotics were previously the only treatment for the chlamydia-ridden tree-dwellers but it disrupted their digestive abilities and did not protect against future infections.
Chlamydia was first observed in koalas about 50 years ago.
The bacterial infection causes blindness, bladder infections, infertility, and death.
The disease has taken a heavy toll on Australia’s koala population.
The native species are shy and notoriously difficult to count, but the government considers the animal as endangered along the east coast.
Australia’s official national monitoring programme estimates between 95,000 and 238,000 koalas live in the eastern states of Queensland, New South Wales and the Australian Capital Territory.
Another 129,000 to 286,000 of the marsupials are estimated to be living in Victoria and South Australia.
Expanding cities, land clearance, and the spread of chlamydia are devastating the populations of one of Australia’s most well-loved animals.
Scientists believe Australia has the highest rate of mammal extinction in the world, with about 100 of the country’s unique flora and fauna species wiped out in the past 123 years.
Australia halted logging in a large stretch of the eastern coast on Sunday to create a retreat for koalas and save the local population from extinction.
-Agence France-Presse