Interestingly, Australia does have cases of two of these pathogens. According to the State of Queensland's official website, anthrax is detected occasionally in southern Queensland as recently as 2018 and botulism commonly occurs in livestock in phosphorus deficient areas of northern Australia. Australia is declared free of rabies, however, a similar lyssavirus (the genus of virus to which rabies belongs) that is found in bats is present in Australia. (Being free of rabies means that the area has had no deaths from rabies for several years.)

So, let's go one by one through these diseases, starting with rabies. Australia has a strict system in which they have partnered with other countries and international organizations to detect, prepare, respond, and recover from potential rabies and other emerging infectious diseases. They also hold annual surveys on all dogs in the outer Torres Strait Islands and request indigenous rangers to report on the health status of animals in their community to develop baseline data and detect early signs of rabies outbreak . So, although there are no vultures in Australia to consume and remove animal carcasses, rabies virus is not prevalent in the first place, due to good management and preventative care.

As a side note, even though Australia lacks the iconic scavengers that are vultures, they have their own native species of scavengers to reduce the spread of disease. Mammalian scavenging species include dingoes, red foxes, feral cats and feral pigs. Avian species include corvids like crows and ravens, and a paper from 2017 by Peisley et al.[1] notes that many raptors like the Wedge-tailed Eagle and Whistling Kite have important roles in the breakdown and removal of carrion.

Let's talk about botulism next. Botulism is a rare illness caused by the neurotoxins produced by Clostridium botulinum under low-oxygen conditions, a bacteria which is commonly found in soil and water. It is most often spread through food containing the toxin when eaten, when spores from the bacteria enter a wound and release the toxin, or when the bacteria develops in the intestines of infants and releases the toxin. Having said that, please note that botulism is still fairly rare. In any case, botulism is kept in check through good food hygiene, making sure to keep things clean, inactivating the bacterium by acidifying and heat-sterilizing canned foods.

Botulism outbreaks in Australia are mostly found in cattle and sheep especially during droughts and in phosphorus-deficient areas when the livestock try to satisfy their craving for phosphorus and/or protein by eating bones and carrion.[2] They have since passed legislation to prohibit feeding animal matter and denying access to this material to livestock. A range of botulism vaccines are also available to reduce botulism outbreaks.

Finally, anthrax, a bacterial disease from Bacillus anthracis. Outbreaks of anthrax occur in animals from time to time, however, the last confirmed human case of anthrax in Australia occurred in 2010, from a skin infection caused by exposure to anthrax spores.[3] Anthrax is controlled by isolating farms with suspected cases, vaccinating herds, and appropriately disposing of animals to minimize soil contamination.

So even without vultures to run damage control and corpse removal, Australia has its own scavengers and procedures meant to deal with pathogens and outbreaks effectively!

References:
[1] Rebecca K. Peisley, Manu E. Saunders, Wayne A. Robinson & Gary W. Luck (2017) The role of avian scavengers in the breakdown of carcasses in pastoral landscapes, Emu - Austral Ornithology, 117:1, 68-77, DOI: 10.1080/01584197.2016.1271990 ↩︎
[2] Gurnett, M. (Sept. 26, 2019). Queensland Country Life - Southern Edition , p. 24. ↩︎
[3] “Anthrax.” Health Conditions Directory , The State of Queensland, 19 June 2019, conditions.health.qld.gov.au/HealthCondition/condition/14/33/8/anthrax. ↩︎