A new vaccine could help curb one of the country's biggest koala killers, with experts hoping the injection could protect the species from future extinction.
Experts estimate over half of New South Wales and Queensland's koala populations are sick with chlamydia, and researchers have worked for over a decade to create a vaccine.
Dr Michael Pyne from Currumbin Wildlife Hospital said of 500 koalas admitted to the Gold Coast hospital last year, 60 per cent had the disease.
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"I really do fear if we don't find a way to manage chlamydia disease there will certainly be a loss of a number of koalas," he said.
Clinical trials for the vaccine initiated by the University of the Sunshine Coast began in October last year.
At the Currumbin Wildlife Hospital, 155 koalas have received their jab.
One koala patient named Kassidy is now healthy and nursing a joey.
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"We actually suspected that the boys were very interested in her so we've been following her closely and we re-caught her recently and she had a little two-month-old joey in the pouch," Dr Pyne said.
The hospital is currently monitoring eleven of its released koalas closely, and all have remained chlamydia-free.
The hope is that the vaccine can be administered on a larger scale, protecting koalas from the infection.
"The hope is that this can be rolled out in a much bigger way," Dr Pyne said.
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"The goal is exactly finding out where that threshold is of how many koalas do we need to vaccinate to stabilise things and get the reproductive rates creeping back up."
Source: 9News