Abstract
Australian native fauna have long been recognised for their susceptibility to infection with Toxoplasma, often suffering serious clinical consequences. There have also been anecdotal suggestions that Toxoplasma could have caused die-offs of native fauna in the past, and that the source of such infections was likely to be cats introduced by Europeans. However, much of our understanding relates to the consequences of infection in captive animals. There are few data on the prevalence and impact of Toxoplasma in free ranging wildlife. We present data suggesting that Toxoplasma infection is associated with the decline of woylies in the south-west of Western Australia. Further, the molecular characterisation of Toxoplasma isolates from marsupials has demonstrated the occurrence of novel ‘trains’ thus questioning the origin of Toxoplasma in Australia.