A young wild koala named Bamse — Norwegian for "teddy bear" — has made history as the first koala to receive a revolutionary chlamydia vaccine implant, marking a potential turning point in efforts to save one of Australia's most iconic species.
Captured from a wild population in Burleigh, Queensland, the 18-month-old female was brought to Currumbin Wildlife Hospital, sedated, vaccinated, and released back into the wild on the same day — sporting a GPS tracking collar. Since then, four more koalas have received the same treatment. When Bamse and one other koala were later recaptured and assessed, both were found completely chlamydia-free.
"Bamse was a great candidate, a young female koala, the poster child for the future of the species," said Dr. Michael Pyne OAM, Senior Vet at Currumbin Wildlife Hospital. "To protect her with the vaccine implant is exactly what we want to be doing. We'll be monitoring her over the next six months. It'll be exciting to see her when she gets her first joey."
The new treatment is significant not just for what it does, but for how it is delivered. Australia's koalas have been vaccinated against chlamydia before — more than 500 have received single doses at Currumbin and the Moggill Koala Rehabilitation Centre. But that earlier protocol required recapturing each animal four weeks later for a second booster injection, placing enormous stress on notoriously shy wild animals and straining conservation resources.
The new method, developed by scientists at Queensland University of Technology (QUT), solves this elegantly: a second dose is embedded in a small biodegradable implant that breaks down over 30 days, gradually releasing the booster while the koala goes about its normal life. Both doses are now administered in a single examination — no second capture needed.
"We've been working with vaccines against chlamydial disease in koalas for over five years now, and this is a massive breakthrough — turning a two-injection vaccine into an injection and an implant that can be all applied in one examination," said Dr. Pyne. "It's truly a remarkable moment."
Chlamydia is no minor inconvenience for koalas. Around 50% of Australia's remaining koalas are infected, though rates vary dramatically between populations — some groups are relatively clear, while others see up to 90% infection. The disease can cause blindness and, critically, infertility in females — a devastating blow to an already struggling species whose populations are increasingly fragmented by habitat loss.
The results in South East Queensland have been striking. In 2020, more than 70% of koalas from one population treated at Currumbin had chlamydia. Now, infection is down an estimated 75%, and the community has seen the birth of 41 joeys and 13 grand-joeys — a genuine recovery that offers real hope.
"We've seen such devastation from chlamydial disease in koalas in South East Queensland and New South Wales," said Dr. Pyne. "It's absolutely critical the vaccine is rolled out en masse to at-risk populations to protect them. But the progress we've made is truly exciting — it gives us hope and allows us to think there is a way to save koalas."
The news builds on last year's approval of Australia's first koala chlamydia vaccine. The implant format now makes it feasible to vaccinate at the scale the crisis demands. For Bamse, already back in the wild and being tracked, the future looks bright. And for Queensland's koalas, this world-first may be the beginning of a real comeback.
