Thesis proposal review: The epidemiology of shigellosis in Australia


Shigellosis is a type of gastroenteritis caused by the Shigella bacterium. Globally, Shigella species are a leading cause of diarrheal mortality, accounting for over 200,000 deaths in 2016. In Australia, there has been an increasing trend in the notification rate of shigellosis, with recent outbreaks being reported in Aboriginal and Torres Strait Islander communities, and among men who have sex with men (MSM). Antimicrobial resistance (AMR) in Shigella strains is also an increasing concern both globally and in Australia, with drug resistance reported as a common characteristic in Shigella infections in MSM and returned travelers.

Over the past 10 years, there has been a shift in the testing methods used to diagnose shigellosis, with an increasing uptake of culture independent diagnostic testing (CIDT). While CIDT methods are more sensitive than traditional bacterial culture methods, the ability to obtain more in-depth information, such as antimicrobial susceptibility and epidemiological typing, is compromised.

The aim of this PhD is to improve understanding of the epidemiology of shigellosis in Australia, and the impact of changing testing practices on Shigella surveillance. The outcomes of the research will contribute to enhancing shigellosis surveillance and outbreak investigations, and to implementing targeted and efficient prevention measures. The research questions that will be addressed in this PhD are:

  1. What are the epidemiological trends of Shigella species in Australia over the past 20 years?
  2. What are the risk factors and genomic characteristics of Shigella boydii in Australia?
  3. What are the implications of CIDT on Shigella surveillance?
  4. What are the trends in antibiotic resistant Shigella in Australia?



Aaliya Ibrahim is a part-time PhD Candidate at the National Centre for Epidemiology and Population Health. Prior to commencing her PhD, she completed a Bachelor of Medical Science (ANU) and Master of Clinical Epidemiology (UoN). Aaliya has experience working as an epidemiologist and policy officer in the Australian Government, focussing on a range of public health issues including communicable diseases, antimicrobial resistance, and environmental health. While undertaking her PhD, Aaliya is working as an Assistant Director in the Research and Product Review Team at the National Blood Authority.