CEE Seminar - The Protist Paradox: Dual Role in Waterborne Pathogen Control

Protists are ubiquitous in every water compartment, including drinking water, surface water, and wastewater. While many studies investigated the removal of pathogenic protists, the role of non-pathogenic protists has received less attention with respect to water quality. Yet, they are crucial in waterborne pathogens' fate throughout the food chain and host-microbe interactions.
The interaction between protists and waterborne pathogens can lead to drastically different outcomes, ranging from removal or loss of infectivity to protection from external stressors or increased pathogen concentration.
It is critical to understand why and how one of those scenarios occurs if one wants to engineer remediation systems and to include protists' action in water quality predictive model tools to ensure microbial safety and prevent the spread of infectious diseases. In this work, we explore the abiotic and biotic factors that modulate the fate of waterborne viruses (with a focus on enteric viruses) and bacteria (with a focus on opportunistic pathogens) upon interactions with protists using microcosm settings. We also discuss the underlying mechanisms leading to one positive or negative outcome for water microbial safety.