Publications by authors named "M W LeChevallier"

In contrast to "frank" pathogens, like , , and , that always have a probability of disease, "opportunistic" pathogens are organisms that cause an infectious disease in a host with a weakened immune system and rarely in a healthy host. Historically, drinking water treatment has focused on control of frank pathogens, particularly those from human or animal sources (like , , or ), but in recent years outbreaks from drinking water have increasingly been due to opportunistic pathogens. Characteristics of opportunistic pathogens that make them problematic for water treatment include: (1) they are normally present in aquatic environments, (2) they grow in biofilms that protect the bacteria from disinfectants, and (3) under appropriate conditions in drinking water systems (e.

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Simultaneous nitrification and denitrification under low dissolved oxygen conditions is an energy-saving modification of the activated sludge process to achieve efficient nitrogen removal. Geographically distinct full-scale treatment plants are excellent platforms to address the links of microbial community with operating parameters. Mixed liquor samples were collected from a sequencing batch reactor plant, oxidation ditch plant, and step-feed activated sludge plant.

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The 2013-2016 Ebola epidemic revived concerns about infection risks to wastewater workers. Prior research has shown that wastewater can contain a variety of known and emerging pathogens and that wastewater workers are at increased risk of infectious illnesses. However, guidelines on using personal protective equipment (PPE) to decrease these risks are lacking.

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Now is an opportune time to foster collaborations across sectors and geographical boundaries to enable development of best practices for drinking water (DW) microbiome research, focusing on accuracy and reproducibility of meta-omic techniques (while learning from past microbiome projects). A large-scale coordinated effort that builds on this foundation will enable the urgently needed comprehensive spatiotemporal understanding and control of DW microbiomes by engineering interventions to protect public health. This opinion paper highlights the need to initiate and conduct a large-scale coordinated DW microbiome project by addressing key knowledge gaps and recommends a roadmap for this effort.

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