Dr Sopheak Hem

Using her expertise in clinical microbiology, infectious diseases, genomic epidemiological microbiology and risk assessment, Dr Sopheak Hem is tackling the complex challenges of environmental AMR.

Q: How did you end up studying antimicrobial resistance (AMR)?

Sopheak: My interest in AMR began before I even knew what AMR was. Growing up in the countryside in the southern part of Cambodia, which is known for its stunning natural beauty, I was always curious about nature and the environment. Unfortunately, as a lower-middle income country, Cambodia had limited healthcare and hygiene, particularly in the decades following the civil war and the Khmer Rouge genocide. I saw how people, animals and the environment were affected by infections that could not be easily cured. That inspired me to study microbes, infectious diseases, and eventually AMR.

I completed a dual doctoral degree in clinical microbiology and infectious diseases from the University of Health and Sciences in Cambodia and Paris Descartes University in France. Then I earned a PhD in genomic epidemiological microbiology from the University of Technology Sydney, focusing on AMR in water environments.

My previous work mostly highlighted AMR problems and raised awareness, but SAAFE offers the chance to be part of real solutions.

Q: You’re part of the AMR Risk Management project, which focuses on better control of AMR in the environment. What does your work involve?

Sopheak: My research aims to investigate the effects of disinfection on opportunistic bacteria inhabiting free-living amoebae to identify effective strategies for controlling pathogen spread. Amoebae, which are common in our water systems, provide a protective environment that allows bacteria to survive inside them, making them more difficult to eliminate. I am studying the interactions between amoebae such as Acanthamoeba polyphaga, Vermamoeba vermiformis and Willaertia magna and bacteria including Acinetobacter baumannii, Pseudomonas aeruginosa and other ESKAPE pathogens. These bacterial species are recognised by the World Health Organization as emerging public health threats.

This involves studying how disinfectants such as free chlorine, monochloramine and ultraviolet light affect bacteria living within free-living amoebae and their ability to develop AMR genes. By determining the concentrations and exposure times at which disinfectants effectively kill or reduce the bacteria, I hope to contribute to the development of strategies to limit pathogen spread and protect public health.

Q: What other SAAFE projects are you working on?

Sopheak: I’m currently involved in a SAAFE Kickstart project to develop a point-of-use diagnostic tool for detecting Listeria monocytogenes in food and environmental samples, which is aimed at improving risk management and food safety.

I’m also part of an exciting project to build capacity for AMR solutions. We are co-developing a design-thinking toolkit with the University of Queensland, the United Nations Environment Programme and partners across the Asia-Pacific to support culturally appropriate training in AMR management for high-, middle- and low-income settings.

Q: You started your career studying emerging AMR in humans. Has expanding your research expertise to include the environment changed the way you think about AMR?

Sopheak: Moving from Cambodia to Australia was a turning point for me, shifting my focus from human public health to environmental science. This change allowed me to completely explore the connections between humans, animals and the environment through a One Health perspective.

Solving AMR is not one sector’s job – it requires building bridges between humans, animals and the environment, guided by shared knowledge, experiences and coordinated action.

One of the most exciting parts of my current work is observing how microbes can become more resistant to antimicrobials and multiple stresses, including disinfectants, when they co-exist. It’s fascinating, because it reflects our real lives, showing that we generally become stronger when we work together.