Hepatitis E virus (HEV) is a non-enveloped single-stranded positive-sense RNA virus, belonging to the Hepeviridae family, resistant to environmental conditions, and transmitted by the consumption of contaminated water. This virus is responsible for both sporadic and epidemic outbreaks, leading to thousands of infections per year in several countries, and is thus considered an emerging disease in Europe and Asia. This study refers to a survey in Portugal during 2019, targeting the detection and eventual quantification of enteric viruses in samples from surface and drinking water. Samples positive for HEV RNA were recurrently found by reverse transcription quantitative PCR (RT-qPCR), in both types of matrix. The infectivity of these samples was evaluated in cultured Vero E6 cells and RNA from putative viruses produced in cultures evidencing cytopathic effects and was subjected to RT-qPCR targeting HEV genomic RNA. Our results evidenced the existence of samples positive either for HEV RNA (77.8% in surface water and 66.7% in drinking water) or for infectious HEV (23.0% in surface water and 27.7% in drinking water). These results highlight the need for effective virological control of water for human consumption and activities.

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Monitoring the quality of water is a requisite to prevent outbreaks related to waterborne diseases, predominantly caused by pathogens like enteric viruses, usually transmitted via the fecal-oral route. This study aimed to survey a group of enteric viruses (Enterovirus, Norovirus genogroups I and II, and hepatitis A virus) in two surface water sources of drinking water, also intending to evaluate the extent of their elimination in the two water treatment plants (WTPs) involved in drinking water production. Correlations between these viruses and fecal indicator bacteria (FIB) were also evaluated. Positive samples for viral RNA were recurrently found by reverse transcription quantitative PCR (RT-qPCR) and quantified, in genomic copies per liter (gc/L) of sampled water. Viral RNAs were detected in 14 out of 27 samples of surface water, and 21 out of 36 samples of drinking water, NoV II having been the most frequently detected in both (0–78.6 gc/L and 0–12.5 gc/L, respectively). Both WTPs showed variable efficacies in the elimination of viral RNA. Only one correlation was found with FIB, between NoV II and intestinal enterococci. These results recommend the monitoring of enteric viruses over time and their inclusion in the mandatory analysis of water quality.

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This paper presents the design features of a dynamic security assessment (DSA) system. The main issues regarding DSA system functionalities, security assessment methodologies, numerical algorithms, technical specification, and system architecture are discussed. Performance results of the real-time static security assessment are presented.Index Terms--dynamic security assessment, high performance computing, distributed processing system. 7 X. BIOGRAPHIES . He worked for a consulting (Themag) and a utility (Furnas Centrais Eletricas) company and for a research center (CEPEL) in Brazil. He worked also for a utility company (BCHydro) in Canada. At present he is a consultant for ONS, Operador Nacional do Sistema (Brazilian ISO). He is a member of IEEE. He has worked with power systems applications development and studies in planning and operation areas. Wes T. Kwasnicki (M'85) received his M.Sc. degree in Applied Mathematics from the Wroclaw University of Technology, Poland in 1979. He also received the M.Sc. and Ph.D. degrees in Electrical and Computer Engineering from the University of Manitoba, Canada in 1986 and 1998 respectively. He has worked for the Manitoba HVDC Research Centre (Winnipeg, Canada) between 1986 and 1999 where he was engaged in studies of various aspects of power systems, power electronics, applications of artificial intelligence, and development of electromagnetic transients simulation and high speed transient stability programs. At present he is a Senior Engineer with the British Columbia Transmission Corporation (Vancouver, Canada). He is a member of IEEE and a registered Professional Engineer in the Province of British Columbia.

Water quality monitoring is a fundamental tool in the management of freshwater resources. The purpose of monitoring is to provide meaningful quality data for local action planning and catchment-wide decision making. The assessment of water quality is crucial to guarantee the efficient operation of the Water Treatment Plants (WTPs), promoting health conditions and contributing for a more sustainable urban water cycle. In accordance, the objective of this study was to evaluate key target chemical and microbiological water quality parameters, some of them already monitored within Portuguese/EU legal framework and others still not regulated, but with environmental and human heath relevance. A local monitoring database model, using a 6-year period (from 2014 to 2019) of water quality data, regarding water samples collected on representative sampling locations covering the freshwater abstraction sites, conventional WTPs and distribution network was assessed. This work provides new knowledge regarding occurrence and seasonal behaviour for both microbiological and chemical water quality parameters, essential to understand/manage the water supply system. Additionally, relationships between the target variables were also assessed. Particularly, strong correlations were identified between TOC and THMs formation at distribution network (r = 0.69; p ≤ 0.001); nitrates were the water quality parameter that revealed the best correlation between surface water source and treated water (r = 0.81; p ≤ 0.001), suggesting that treatment yield/performance is dependent on surface water load. The local and continuous monitoring of water systems are crucial to implement new approaches to guarantee the best quality of drinking water throughout the supply system.

The present study, developed in the scope of a survey to monitor enteric viruses in natural surface water and drinking water sources, addressed the suitability of mengovirus to assess viral recovery rates at two steps of the water sampling process. In a pilot campaign comprising two samples from each type of water source, when mengovirus was added after the filtration/primary concentration step, the recovery rates of viral RNA were higher than 18% and identical for both water matrices. In a one-year sampling campaign, where mengovirus was present along the whole sample processing (addition in the filtration/primary concentration step), significantly different recovery rates were observed between water matrices: usually higher than 1% in drinking water and under 1% in surface water. The results suggest the first stage of the water sampling process and the type of water matrix are the most influential factors for viral RNA recovery. This study also addressed and evidenced mengovirus replication and titration in Vero E6 cultures and showed infectious mengovirus to be recovered from samples of both types of water matrix. These results anticipate a more comprehensive applicability of mengovirus as a process control virus in the monitoring of viruses in water, extended to viral infectivity.

Water-related infectious diseases are important causes of morbidity and mortality. Enterovirus and Hepatitis A and E viruses are, among others, representative of the enteric viruses, which are disease-causing agents mainly transmitted by the oral-fecal route, through water. The objective of this study is to search for enteric viruses by reverse transcription followed by Real-time PCR (RT-qPCR), in samples of natural surface water and in drinking water. It is also intended to evaluate the eventual association of these viruses with other fecal contamination indicators, and the efficacy of the water treatment plants in their elimination. It was confirmed the adequacy of the methodology implemented since, in the 15 samples analyzed so far, Hepatitis A virus and Enterovirus RNAs were detected in natural surface water samples, in two and three samples, respectively. Both viruses RNAs were detected in one of these samples. No viral nucleic acids were detected in drinking water samples. Fecal coliforms (microbial indicators of fecal contamination) were detected in natural water samples, but not in drinking water samples. Viral RNA and coliform detection only partially co-occurred.