Australian researchers have developed a vaccine for koalas to combat an extensive outbreak of sexually transmitted diseases in the species. Koala’s, which have been hit hard by changing climatic conditions, bushfires, and land clearing, are under pressure from an ongoing chlamydia outbreak that is causing the marsupials to become infertile and further pushing the species towards potential extinction. The senior veterinarian at the Currumbin Wildlife Hospital, Dr. Michael Pyne, said he had witnessed a significant growth in the number of koalas admitted to his hospital over his career. “I first started working at the hospital 20 years ago; it was unusual to see a koala admitted. We probably only saw about two or three per year,” Pyne said. “Fast-forward 20 years, and we are admitting up to 500 koalas annually. It’s heartbreaking to see the problems our koalas are facing.” Of the 500 koalas admitted annually, 60 percent are sick or dying from …