The incidence and significance of certain common diseases in local native wildlife is assumed knowledge in the veterinary profession. Sometimes less widely known however, are the opportunities that exist for general practitioners to actively contribute to the research and management programs that will help with the control of these diseases.

One such example is chamydiosis in koalas.  Chlamydia is an insidious infection, most commonly causing ocular or urogenital tract disease, typically in older sexually active koalas [1]. The disease has significant welfare implications for affected individuals, and is considered likely to impact koala populations, especially as climatic and habitat pressures increase [2]. End stage chlamydial ocular disease results in chronic keratoconjunctivitis, blindness and on occasion, rupture of the globe [1]. Urogenital disease is associated with acute or chronic cystitis, urethritis and/or nephritis, and inflammatory changes to the reproductive tract that may result in infertility [1,2].

Koalas may also have subclinical infections, and many studies have indicated the disease may be prevalent in populations despite low incidence of overt disease [1]. PCR testing of swabs from urogenital and conjunctival sites has proven valuable for detecting subclinical disease [1] and is easily achieved in clinical practice, as demonstrated in this video by Dr Shivananden Sawmy of the University of Sydney’s Avian, Reptile and Exotic Pet Hospital.

Critically, recent studies have suggested that population wide treatment of infected koalas together with strategic euthanasia of terminally diseased and infertile animals could virtually eliminate chlamydial infection and promote population growth within a 4-year period [1]. Passive disease surveillance through collection of opportunistic data and samples from koalas under veterinary care is considered best practice [3] – and if it is widely undertaken, could play a significant role in helping to control this debilitating disease in a much loved and vulnerable species.

About the Presenter

Dr Shivananden Sawmy is an experienced wildlife and exotic veterinarian who has worked in exotic and small animal practice across the UK, as well as with critically endangered wildlife as a field biologist in his native Mauritius. Now based at the University of Sydney’s Avian, Reptile and Exotic Pet Hospital, he enjoys working with the full range of Australian native animals and is a highly regarded mentor for veterinary students undertaking their practical training at the hospital.

Need to know more?

The Koala Health Hub (an initiative of the University of Sydney) has a terrific written protocol for Chlamydia swab collection, available at http://koalahealthhub.org.au/fact-sheets. The website provides fantastic resources for all aspects of koala husbandry and veterinary care, including health examination records and charts, treatment tables, and information on common diseases.

The definitive text Current Therapy in Medicine of Australian Mammals (see references below) has recently been released and has several detailed chapters on koala medicine, including a dedicated chapter on chlamydiosis.

The University of Sydney’s Avian, Reptile and Exotic Pet Hospital is currently raising money for animals in need, including those affected by the recent bush fires, for which they receive no funding. Please see https://crowdfunding.sydney.edu.au/bushfirevetappeal to donate today.

 

References

[1] Vogelnest, L. and Portas, T. (eds). Current Therapy in Medicine of Australian Mammals, Clayton South, CSIRO Publishing, 2019, pp495-506

[2] Talbot, B. Some common injuries and diseases of koalas [Website], http://koalahealthhub.org.au/fact-sheets (accessed 12 February 2020)

[3] Koala Health Hub. Koala clinical examination[Website], http://koalahealthhub.org.au/sampling-protocols (accessed 12 February 2020)