(David Gray | AFP via Getty Images)A vaccine has been approved to help protect koalas against chlamydia, a measure researchers are hailing as a world-first in fighting the disease that is a leading cause of death for the beloved marsupials. In Australia, scientists begin vaccinating koalas against chlamydia The safety and effectiveness of the vaccine, designed specifically for koalas, has previously been tested by vaccinating a few hundred koalas brought to wildlife rescue centers for other afflictions. Chlamydia in koalas can cause blindness and lead them to starve to death because they cannot locate trees to climb for food, according to Koala Conservation Australia. Sam Phillips, a senior researcher at the UniSC, said the vaccine has been tested on hundreds of wild koalas and koalas in captivity. The agency told NPR it approved a permit authorizing use of the vaccine in koalas in June that runs through June 2027.