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INTRODUCTION
The increasing contamination of water resources contributes to the unsustainability of water use worldwide. Climate change has exacerbated this situation, and it is expected that in some countries the predicted reduction in rainfall or alterations in the hydrological system may create or aggravate situations of water scarcity or stress (WATEFCON 2014). Among water resources, coastal lagoons are considered socially and economically important due to their intensive use by humans and animals as water resources, sanitation tools and areas for swimming and recreation. Brazilian coastal lagoons are subjected to several types of anthropogenic uses and influences due to population pressure, contributing to the degradation of their water quality (Branco et al. 1998; Petrucio 1998; Hennemann & Petrucio 2011). Indeed, lagoon surface waters, which are used for human consumption and recreational activities, are being contaminated by human and animal pathogens. These pathogens include enteric viruses, which replicate in the gastrointestinal tract, are excreted in feces at extremely high concentrations (ranging from 105-1013 viral particles per gram of stool), and often enter sewage (Bosch et al. 2008). This contamination occurs mainly as a result of unregulated direct or indirect discharge of domestic polluted sewage or its runoff from surrounding populations into lagoons (Donovan et al. 2008; Fongaro et al. 2014). Viruses are difficult to detect in all aquatic matrices and are often associated with non-specific infections. In addition, viral epidemiology is usually difficult, as many cases of viral infections are not reported to medical authorities, which makes tracing the causes of outbreaks a challenging task (Percival et al. 2004). Nevertheless, the contamination of surface water by enteric viruses is a major public health concern related to water resources used for drinking and recreational purposes. This is due to the risks caused by these viruses, which can be acquired by drinking the water, by immersion in recreational water or by skin contact or inhalation if the water has been contaminated with sewage. The fate of these pathogens in the aquatic environment after they have been released into the surface water is controlled by sorption-desorption processes (Wong et al. 2012, 2013). Due to their size, colloidal particles appear to be the most important natural vehicle for suspended viruses in the water column, which occurs as a result of this...