Western Australian Marsupials Are Multiply Infected with Genetically Diverse Strains of Toxoplasma gondii

Abstract

Five different organs from 16 asymptomatic free-ranging marsupial macropods (Macropus rufus, M. fuliginosus, and M. robustus) from inland Western Australia were tested for infection with Toxoplasma gondii by multi-locus PCR-DNA sequencing. All macropods were infected with T. gondii, and 13 had parasite DNA in at least 2 organs. In total, 45 distinct T. gondii genotypes were detected. Fourteen of the 16 macropods were multiply infected with genetically distinct T. gondii genotypes that often partitioned between different organs. The presence of multiple T. gondii infections in macropods suggests that native mammals have the potential to promote regular cycles of sexual reproduction in the definitive felid host in this environment.

Diverse Applications of Environmental DNA Methods in Parasitology

“…Many RT-qPCR assays have been developed, for example for the fish parasites Ichthyobodo and Ichthyophonus [57,58], the myxozoan parasite Ceratonova (previously Ceratomyxa) shasta in rivers [59], screening marsupials for Toxoplasma gondii [60], and monitoring of intranuclear coccidian parasites in endangered turtles [61]. For very well studied groups or systems, such as Cryptosporidium, Giardia, and Enterocytozoon, the molecular tools have become diverse and refined; for example, allowing identification of differently distributed genetic subtypes in wastewater samples [62] and using quantification to estimate transmission risk [63].…”

Parasite zoonoses and wildlife: One health, spillover and human activity

“…As with Trichinella, research over the last decade has demonstrated that Toxoplasma is far more prevalent in wildlife than previously considered, and affects a huge diversity of species, both terrestrial and marine mammals and birds, in all environments studied including the Arctic (Wendte et al, 2011;Pan et al, 2012;Jenkins et al, 2013). In addition, as more isolates from wildlife are characterised genetically using multiple loci, what is also apparent is the great genetic diversity of Toxoplasma in wildlife and the occurrence of novel genotypes which differ from the 'standard' domestic strains (Ajzenberg et al, 2004;Wendte et al, 2011;Pan et al, 2012). These observations raise many questions about the ecology of Toxoplasma infections in wildlife ecosystems and how it differs from that in domestic ecosystems from which we have obtained most of the information on which we have based our understanding of the population dynamics and transmission.…”

“…Firstly, little is known about the virulence of strains of Toxoplasma that are maintained in wildlife populations. Available evidence would suggest that they are largely avirulent in natural ecosystems (Thompson et al, 2010a;Pan et al, 2012). Toxoplasma is prevalent in wildlife ecosystems and exhibits a high level of genetic variation.…”

“…However, in other environments it is difficult to understand how environmental contamination can be the sole source of infection in wildlife ecosystems. This is certainly the case in arid areas where felid hosts are not common, for example in parts of Australia where high levels of infection occur in native marsupials (Pan et al, 2012). Under such circumstances, the maintenance of infection by vertical transmission cannot be dismissed in the face of mounting epidemiological evidence from both wild and domestic ecosystems (Hide et al, 2009;Parameswaran et al, 2009).…”

Wild Mammal Translocations: A Public Health Concern

“…Australia [55] Red Kangaroo Macropus rufus Toxoplasma gondii Australia [60] Eimeria toganmainensis Australia [59] Eimeria wilcanniensis Australia [59] Eimeria macropodis Australia [59] Leishmania spp Australia [61] Western grey kangaroo…”