Browsing by Author "Sadowsky, Michael J."
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- Beach sand and the potential for infectious disease transmission: observations and recommendationsPublication . Solo-Gabriele, Helena M.; Harwood, Valerie J.; Kay, David; Fujioka, Roger S.; Sadowsky, Michael J.; Whitman, Richard L.; Wither, Andrew; Caniça, Manuela; Carvalho da Fonseca, Rita; Duarte, Aida; Edge, Thomas A.; Gargaté, Maria J.; Gunde-Cimerman, Nina; Hagen, Ferry; McLellan, Sandra L.; Nogueira da Silva, Alexandra; Novak Babič, Monika; Prada, Susana; Rodrigues, Raquel; Romão, Daniela; Sabino, Raquel; Samson, Robert A.; Segal, Esther; Staley, Christopher; Taylor, Huw D.; Veríssimo, Cristina; Viegas, Carla; Barroso, Helena; Brandão, JoãoRecent studies suggest that sand can serve as a vehicle for exposure of humans to pathogens at beach sites, resulting in increased health risks. Sampling for microorganisms in sand should therefore be considered for inclusion in regulatory programmes aimed at protecting recreational beach users from infectious disease. Here, we review the literature on pathogen levels in beach sand, and their potential for affecting human health. In an effort to provide specific recommendations for sand sampling programmes, we outline published guidelines for beach monitoring programs, which are currently focused exclusively on measuring microbial levels in water. We also provide background on spatial distribution and temporal characteristics of microbes in sand, as these factors influence sampling programs. First steps toward establishing a sand sampling program include identifying appropriate beach sites and use of initial sanitary assessments to refine site selection. A tiered approach is recommended for monitoring. This approach would include the analysis of samples from many sites for faecal indicator organisms and other conventional analytes, while testing for specific pathogens and unconventional indicators is reserved for high-risk sites. Given the diversity of microbes found in sand, studies are urgently needed to identify the most significant aetiological agent of disease and to relate microbial measurements in sand to human health risk.
- Climate Change Impacts on Microbiota in Beach Sand and Water: Looking AheadPublication . Brandão, João; Weiskerger, Chelsea; Valério, Elisabete; Pitkänen, Tarja; Meriläinen, Päivi; Avolio, Lindsay; Heaney, Christopher D.; Sadowsky, Michael J.Beach sand and water have both shown relevance for human health and their microbiology have been the subjects of study for decades. Recently, the World Health Organization recommended that recreational beach sands be added to the matrices monitored for enterococci and Fungi. Global climate change is affecting beach microbial contamination, via changes to conditions like water temperature, sea level, precipitation, and waves. In addition, the world is changing, and humans travel and relocate, often carrying endemic allochthonous microbiota. Coastal areas are amongst the most frequent relocation choices, especially in regions where desertification is taking place. A warmer future will likely require looking beyond the use of traditional water quality indicators to protect human health, in order to guarantee that waterways are safe to use for bathing and recreation. Finally, since sand is a complex matrix, an alternative set of microbial standards is necessary to guarantee that the health of beach users is protected from both sand and water contaminants. We need to plan for the future safer use of beaches by adapting regulations to a climate-changing world.
- Environmental and Adaptive Changes Necessitate a Paradigm Shift for Indicators of Fecal ContaminationPublication . Teixeira, Pedro; Salvador, Daniel; Brandão, João; Ahmed, Warish; Sadowsky, Michael J.; Valério, ElisabeteChanges in the occurrence, distribution, and seasonal variation of waterborne pathogens due to global climate change may increase the risk of human exposure to these microorganisms, thus heightening the need for more reliable surveillance systems. Routine monitoring of drinking water supplies and recreational waters is performed using fecal indicator microorganisms, such as Escherichia coli, Enterococcus spp., and coliphages. However, the presence and numbers of these indicators, especially E. coli and Enterococcus spp., do not correlate well with those of other pathogens, especially enteric viruses, which are a major cause of waterborne outbreaks associated with contaminated water and food, and recreational use of lakes, ponds, rivers, and estuarine waters. For that reason, there is a growing need for a surveillance system that can detect and quantify viral pathogens directly in water sources to reduce transmission of pathogens associated with fecal transmission. In this review, we present an updated overview of relevant waterborne enteric viruses that we believe should be more commonly screened to better evaluate water quality and to determine the safety of water use and reuse and of epidemiological data on viral outbreaks. We also discuss current methodologies that are available to detect and quantify these viruses in water resources. Finally, we highlight challenges associated with virus monitoring. The information presented in this review is intended to aid in the assessment of human health risks due to contact with water sources, especially since current environmental and adaptive changes may be creating the need for a paradigm shift for indicators of fecal contamination.
- Impacts of a changing earth on microbial dynamics and human health risks in the continuum between beach water and sandPublication . Weiskerger, Chelsea J.; Brandão, João; Ahmed, Warish; Aslan, Asli; Avolio, Lindsay; Badgley, Brian D.; Boehm, Alexandria B.; Edge, Thomas A.; Fleisher, Jay M.; Heaney, Christopher D.; Jordao, Luisa; Kinzelman, Julie L.; Klaus, James S.; Kleinheinz, Gregory T.; Meriläinen, Päivi; Nshimyimana, Jean Pierre; Phanikumar, Mantha S.; Piggot, Alan M.; Pitkänen, Tarja; Robinson, Clare; Sadowsky, Michael J.; Staley, Christopher; Staley, Zachery R.; Symonds, Erin M.; Vogel, Laura J.; Yamahara, Kevan M.; Whitman, Richard L.; Solo-Gabriele, Helena M.; Harwood, Valerie J.Although infectious disease risk from recreational exposure to waterborne pathogens has been an active area of research for decades, beach sand is a relatively unexplored habitat for the persistence of pathogens and fecal indicator bacteria (FIB). Beach sand, biofilms, and water all present unique advantages and challenges to pathogen introduction, growth, and persistence. These dynamics are further complicated by continuous exchange between sand and water habitats. Models of FIB and pathogen fate and transport at beaches can help predict the risk of infectious disease from beach use, but knowledge gaps with respect to decay and growth rates of pathogens in beach habitats impede robust modeling. Climatic variability adds further complexity to predictive modeling because extreme weather events, warming water, and sea level change may increase human exposure to waterborne pathogens and alter relationships between FIB and pathogens. In addition, population growth and urbanization will exacerbate contamination events and increase the potential for human exposure. The cumulative effects of anthropogenic changes will alter microbial population dynamics in beach habitats and the assumptions and relationships used in quantitative microbial risk assessment (QMRA) and process-based models. Here, we review our current understanding of microbial populations and transport dynamics across the sand-water continuum at beaches, how these dynamics can be modeled, and how global change factors (e.g., climate and land use) should be integrated into more accurate beachscape-based models.