Antibiotic Resistance in Recreational Waters: State of the Science.

Ambient recreational waters can act as both recipients and natural reservoirs for antimicrobial resistant (AMR) bacteria and antimicrobial resistant genes (ARGs), where they may persist and replicate. Contact with AMR bacteria and ARGs potentially puts recreators at risk, which can thus decrease their ability to fight infections. A variety of point and nonpoint sources, including contaminated wastewater effluents, runoff from animal feeding operations, and sewer overflow events, can contribute to environmental loading of AMR bacteria and ARGs.

Evaluating health risks associated with exposure to ambient surface waters during recreational activities: A systematic review and meta-analysis.

Recreational water quality guidelines protect the public from health risks associated with water recreation by helping to prevent unacceptable concentrations of pathogenic organisms in ambient water. However, illness risk is associated with both the concentration of pathogens in the water and the degree of contact with those pathogens. Different recreational activities can result in different levels of contact with ambient water containing water-borne pathogens.

Comparison of Predicted Microbiological Human Health Risks Associated with de Facto, Indirect, and Direct Potable Water Reuse.

Increasing interest in recycling water for potable purposes makes understanding the risks associated with potential acute microbial hazards important. We compared risks from de facto reuse, indirect potable reuse (IPR), and direct potable reuse (DPR) scenarios using a previously published quantitative microbial risk assessment methodology and literature review results. The de facto reuse simulation results are compared to a spp.

Advancements in mitigating interference in quantitative polymerase chain reaction (qPCR) for microbial water quality monitoring.

The United States Environmental Protection Agency's (EPA) 2012 Recreational Water Quality Criteria included an Enterococcus spp. quantitative polymerase chain reaction (qPCR) method as a supplemental indicator-method. In 2012, performance of qPCR for beach monitoring remained limited, specifically with addressing interference.

Occurrence of coliphage in raw wastewater and in ambient water: A meta-analysis.

Coliphage have been proposed as indicators of fecal contamination in recreational waters because they better reflect the persistence of pathogenic viruses in the environment and through wastewater treatment than traditional fecal indicator bacteria. Herein, we conducted a systematic literature search of peer-reviewed publications to identify coliphage density data (somatic and male-specific, or MSC) in raw wastewater and ambient waters. The literature review inclusion criteria included scope, study quality, and data availability.

Comparison of somatic and F+ coliphage enumeration methods with large volume surface water samples.

Coliphages are alternative fecal indicators that may be suitable surrogates for viral pathogens, but majority of standard detection methods utilize insufficient volumes for routine detection in environmental waters. We compared three somatic and F+ coliphage methods based on a paired measurement from 1 L samples collected from the Great Lakes (n = 74). Methods include: 1) dead-end hollow fiber ultrafilter with single agar layer (D-HFUF-SAL); 2) modified SAL (M-SAL); and 3) direct membrane filtration (DMF) technique.

Potable Water Reuse: What Are the Microbiological Risks?

Purpose Of Review: With the increasing interest in recycling water for potable reuse purposes, it is important to understand the microbial risks associated with potable reuse. This review focuses on potable reuse systems that use high-level treatment and de facto reuse scenarios that include a quantifiable wastewater effluent component.

Recent Findings: In this article, we summarize the published human health studies related to potable reuse, including both epidemiology studies and quantitative microbial risk assessments (QMRA).

Direct potable reuse microbial risk assessment methodology: Sensitivity analysis and application to State log credit allocations.

Understanding pathogen risks is a critically important consideration in the design of water treatment, particularly for potable reuse projects. As an extension to our published microbial risk assessment methodology to estimate infection risks associated with Direct Potable Reuse (DPR) treatment train unit process combinations, herein, we (1) provide an updated compilation of pathogen density data in raw wastewater and dose-response models; (2) conduct a series of sensitivity analyses to consider potential risk implications using updated data; (3) evaluate the risks associated with log credit allocations in the United States; and (4) identify reference pathogen reductions needed to consistently meet currently applied benchmark risk levels. Sensitivity analyses illustrated changes in cumulative annual risks estimates, the significance of which depends on the pathogen group driving the risk for a given treatment train.

Occurrence of norovirus in raw sewage - A systematic literature review and meta-analysis.

Human noroviruses (NoV) are a leading cause of recreational waterborne illnesses and responsible for the majority of viral-associated gastrointestinal illnesses nationwide. We conducted a systematic literature review of published peer-reviewed publications to identify NoV density data in wastewater influent, and provided an approach for developing pathogen density distributions, using the NoV data. Literature review inclusion criteria included scope, study quality, and data availability.

Fractional poisson--a simple dose-response model for human norovirus.

This study utilizes old and new Norovirus (NoV) human challenge data to model the dose-response relationship for human NoV infection. The combined data set is used to update estimates from a previously published beta-Poisson dose-response model that includes parameters for virus aggregation and for a beta-distribution that describes variable susceptibility among hosts. The quality of the beta-Poisson model is examined and a simpler model is proposed.

Bioaccumulation, retention, and depuration of enteric viruses by Crassostrea virginica and Crassostrea ariakensis oysters.

Crassostrea ariakensis oysters are under review for introduction into the Chesapeake Bay. However, the human health implications of the introduction have not been fully addressed. This study evaluated rates of bioaccumulation, retention, and depuration of viruses by Crassostrea virginica and C.

Recovery, bioaccumulation, and inactivation of human waterborne pathogens by the Chesapeake Bay nonnative oyster, Crassostrea ariakensis.

The introduction of nonnative oysters (i.e., Crassostrea ariakensis) into the Chesapeake Bay has been proposed as necessary for the restoration of the oyster industry; however, nothing is known about the public health risks related to contamination of these oysters with human pathogens.

Male-specific coliphages as indicators of thermal inactivation of pathogens in biosolids.

Male-specific (F+) coliphages have been proposed as a candidate indicator of fecal contamination and of virus reduction in waste treatment. However, in this and earlier work with a laboratory thermophilic anaerobic digester, a heat-resistant fraction of F+ coliphage populations indigenous to municipal wastewater and sludge was evident. We therefore isolated coliphages from municipal wastewater sludge and from biosolid samples after thermophilic anaerobic digestion to evaluate the susceptibility of specific groups to thermal inactivation.

Laboratory evaluation of thermophilic-anaerobic digestion to produce Class A biosolids. 2. Inactivation of pathogens and indicator organisms in a continuous-flow reactor followed by batch treatment.

Thermophilic-anaerobic digestion in a single-stage, mixed, continuous-flow reactor is not approved in the United States as a process capable of producing Class A biosolids for land application. This study was designed to evaluate the inactivation of pathogens and indicator organisms in such a reactor followed by batch treatment in a smaller reactor. The combined process was evaluated at 53 degrees C with sludges from three different sources and at 51 and 55 degrees C with sludge from one of the sources.