Abstract
Protozoan parasites remain ubiquitous pathogens for both humans and animals and continue to cause significant morbidity and mortality. Currently, there is a lack of fundamental knowledge on protozoan prevalence and impact on marsupial populations. Here, ectoparasites, blood, and faecal samples were collected from different marsupials and screened by PCR for Giardia, Cryptosporidium, Babesia, Theileria, and trypanosomes. Samples were collected from three locations in Western Australia and Queensland: Kanyana Wildlife Rehabilitation Centre, WA (n=41), Jarrah Forrest near Dwellingup, WA (n=63), Australian Wildlife Hospital, QLD (n=71). About 10% of the wild animals from WA were infected with trypanosomes and Babesia, while Theileria and Cryptosporidium were only detected in about 4% of the sheltered marsupials from Kanyana. Giardia was detected in all groups, at frequencies ranging from 6 to 17%. Sequencing of amplified DNA revealed the presence of novel as well as previously identified protozoan species, some of which were detected in critically endangered species. Phylogenetic trees were constructed based on 18S rDNA (Babesia, Theileria, Cryptosporidium, and Giardia), and 18S rDNA/ GAPDH (trypanosomes). One sheltered boodie (Bettongia lesueur) from Kanyana had a novel Theileria sp., related to T. bicornis (92% identity), which is associated with mortality in black rhinoceros (Diceros bicornis). Seven woylies (Bettongia penicillata) were infected with a novel Babesia sp., most closely related (96% identity) to Babesia species from cattle and an antelope. 18S rDNA/GAPDH trypanosome sequences amplified from woylies and brushtail possums (Trichosurus vulpecula) were 99% similar to sequences previously found in kangaroos. Cryptosporidium macropodum was identified in faecal samples of two sheltered joeys, and Giardia duodenalis assemblage A was detected in various hosts, including koalas and threatened species such as chuditchs, bilbies, and boodies. A better understanding of protozoan parasites infecting marsupials is essential to successfully maintain and manage our marsupial populations, and limit the spread of zoonotic diseases.