A zoonosis is a disease that can be transmitted naturally from animals to humans (WHO 2017): 61% of known human pathogens are zoonotic and 75% of emerging human infectious diseases are zoonoses (Taylor et al. 2001).

The ‘One Health’ concept emphasises the impor­tance of wildlife as a reservoir for zoonotic pathogens and in the transmission of disease to domestic animals and humans (Kruse et al.

Depending on the pathogen involved, zoonoses can be acquired through one or more routes, including direct, indirect or vector transmission. People who have regular or close contact with wildlife are at increased risk of con­tracting a zoonotic disease (Garland-Lewis et al. 2017). This includes veterinarians, veterinary nurses, wildlife researchers, wildlife rehabilitators, conservation program volunteers, wildlife park and zoo animal caretakers, marine mammal rescue volunteers, park rangers and people who handle carcasses or hides of native mammals. Immunocompromised people, including the very young and very old, have a higher risk of infection and may develop more severe disease.

Documented cases of zoonotic disease transmission from an Australian native mammal source are uncom­mon. It is highly likely that many cases go unrecognised or unreported, particularly if the disease causes non-spe­cific signs that could be confused with other common human illnesses or if the course is mild or self-limiting. Some zoonoses are transmitted directly and only have a wildlife host (e.g. Australian bat lyssavirus [ABLV]), while others have a recognised domestic or feral animal host as well as a wildlife reservoir and transmission from a wildlife source may be overlooked (e.g. leptospirosis from introduced rodents or cattle rather than native rodents and Q fever from domestic livestock rather than marsupials). The identification of a zoonotic pathogen in a wild mammal does not guarantee there is a transmis­sion pathway for human infection and, in some cases, the sequence of events leading up to human infection and the role that wildlife plays in disseminating disease may not be understood.

Australian wildlife disease surveillance has increased (Cox-Witton et al. 2014) and it is likely that more zoonotic pathogens will be discovered and transmission pathways and the role played by wildlife as a source of human dis­ease may become clearer.

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