Hurricanes and heavy rains have spawned harmful algal blooms (HABs) caused by aquatic plankton, such as cyanobacteria and dinoflagellates. Climatic and environmental changes often confer selective advantages on environmental pathogens, like aquatic plankton and marine viruses and bacteria, increasing their infectivity and virulence. Prolonged cold spells have precipitated norovirus outbreaks. Low tides, heat waves, and high sea temperatures have resulted in increased reports of human vibrio and mycobacterial soft tissue and systemic infections. This session will improve our understanding of the onset, prevalence, persistence, exposure, and mitigation of toxic and infectious organisms in the aquatic environment. To that end, this session solicits contributions that would improve our understanding of the seasonal occurrence, long-range dependence, and spatiotemporal distribution of the environmental pathogens causing HABs by presenting GeoHealth indicators (e.g., temperature, solar radiation, rainfall, and nutrients), advanced monitoring and detection technologies, effective modeling tools, and exposure-mitigation strategies to protect public health.