Chlamydia is a major threat to koala populations across Australia. This bacterial disease infects between 20% and 90% of individuals in koala populations. It’s a major cause of the rapid decline of many wild populations, particularly in South-East Queensland and northern New South Wales.
Our group at Queensland University of Technology (QUT) has developed two vaccines to target chlamydial infections. One of these vaccines, now being trialled in collaboration with Dr Michael Pyne and his staff at Currumbin Wildlife Hospital, has recently had some outstanding results in a wild koala population on the Gold Coast. This population had been declining rapidly due to high rates of the disease.
Two years into the five-year trial, we have seen more than 25 joeys born to vaccinated females. The program involved vaccinating, collaring and releasing 10-20% of young animals each year. All joeys and mums were chlamydia-free. In addition, 11 out of 13 young males vaccinated remain negative at 12–24 months after vaccination.