Blood Parasites in Endangered Wildlife-Trypanosomes Discovered During a Survey of Haemoprotozoa from the Tasmanian Devil.

Siobhon L Egan,Manuel Ruiz-Aravena,David G Hamilton,Menna E Jones,Sebastien Comte,Peter J Irwin,Xavier Barton,Rodrigo K Hamede,Una M Ryan,Charlotte L Oskam,Jill M Austen

doi:10.3390/pathogens9110873

Abstract

The impact of emerging infectious diseases is increasingly recognised as a major threat to wildlife. Wild populations of the endangered Tasmanian devil, Sarcophilus harrisii, are experiencing devastating losses from a novel transmissible cancer, devil facial tumour disease (DFTD); however, despite the rapid decline of this species, there is currently no information on the presence of haemoprotozoan parasites. In the present study, 95 Tasmanian devil blood samples were collected from four populations in Tasmania, Australia, which underwent molecular screening to detect four major groups of haemoprotozoa: (i) trypanosomes, (ii) piroplasms, (iii) Hepatozoon, and (iv) haemosporidia. Sequence results revealed Trypanosoma infections in 32/95 individuals. Trypanosoma copemani was identified in 10 Tasmanian devils from three sites and a second Trypanosoma sp. was identified in 22 individuals that were grouped within the poorly described T. cyclops clade. A single blood sample was positive for Babesia sp., which most closely matched Babesia lohae. No other blood protozoan parasite DNA was detected. This study provides the first insight into haemoprotozoa from the Tasmanian devil and the first identification of Trypanosoma and Babesia in this carnivorous marsupial.

Highlights

Haemoprotozoan parasites are unicellular eukaryotic organisms with complex lifecycles that involve an invertebrate vector and often alternate in their tropism between the tissues and blood of their vertebrate hosts
All of the samples tested negative for presence of Leishmania, Hepatozoon, Plasmodium, and Theileria species
This wide distribution of Trypanosoma across populations contrasts with the absence of Leishmania, Theileria, Hepatozoon, or Plasmodium species, and the low detection of Babesia, which was only detected in a single individual

Summary

Introduction

Haemoprotozoan parasites are unicellular eukaryotic organisms with complex lifecycles that involve an invertebrate vector and often alternate in their tropism between the tissues and blood of their vertebrate hosts. Four major haemoprotozoan assemblages infect mammals [1]; (i) Trypanosomatids (Kinetoplastea), which are flagellated protists that are characterised by the presence of a unique. Haemoprotozoans are considered either host specific (e.g., Theileria ornithorhynchi infecting the platypus (Ornithorhynchus anatinus) host [2]) or generalists (e.g., Trypanosoma cruzi, which infects a wide range of mammals [3]). The Tasmanian devil, Sarcophilus harrisii, is the largest extant marsupial carnivore. Once present across mainland Australia (~3000 years ago), the distribution of wild populations of Tasmanian devils became restricted to the island of Tasmania [4], off the southern coast of the Australian mainland

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