Parasites of wombats (family Vombatidae), with a focus on ticks and tick-borne pathogens

Ticks (Arachnida: Acari) are vectors for pathogens and the biggest threat to animal health. Many Australian ticks are associated with pathogens that impact humans, domestic animals and livestock. However, little is known about the presence or impact of tick-borne pathogens in native Australian wildlife. Wombats are particularly susceptible to the effects of the ectoparasite Sarcoptes scabiei which causes sarcoptic mange, the reason for which is unknown. Factors such as other ectoparasites and their associated pathogens may play a role. A critical understanding of the species of ectoparasites that parasitise wombats and their pathogens, and particularly ticks, is therefore warranted. This review describes the ectoparasites of wombats, pathogens known to be associated with those ectoparasites, and related literature gaps. Pathogens have been isolated in most tick species that typically feed on wombats; however, there are minimal molecular studies to determine the presence of pathogens in any other wombat ectoparasites. The development of next-generation sequencing (NGS) technologies allows us to explore entire microbial communities in ectoparasite samples, allowing fast and accurate identification of potential pathogens in many samples at once. These new techniques have highlighted the diversity and uniqueness of native ticks and their microbiomes, including pathogens of potential medical and veterinary importance. An increased understanding of all ectoparasites that parasitise wombats, and their associated pathogens, requires further investigation.