Viruses In Water Research Articles

Infectious Pepper Mild Mottle Virus and Human Adenoviruses as Viral Indices in Sewage and Water Samples

The objective of this study was to compare human adenoviruses (HAdVs) genome and infectivity, polyomaviruses (JC and BK) genome (JCPyVs) and (BKPyVs), Pepper Mild Mottle Virus (PMMoV) genome and infectivity, and infectious bacteriophages as viral indices for sewage and water samples. One hundred and forty-four samples were collected from inlets and outlets of water and wastewater treatment plants (WTPs), and WWTPs within Greater Cairo from October 2015 till March 2017. Two methods of viral concentration [Aluminium hydroxide (Al(OH)3) precipitation method and adsorption-elution technique followed by organic flocculation method] were compared to determine which of them was the best method to concentrate viruses from sewage and water. Although samples with only one litre volume were concentrated using Al(OH)3 precipitation method and the same samples with larger volumes (5–20 L) were concentrated using the adsorption-elution technique followed by the organic flocculation method, a non-significant difference was observed between the efficiency of the two methods in all types of samples except for the drinking water samples. Based on the qualitative prevalence of studied viruses in water and wastewater samples, the number of genome copies and infectious units in the same samples, resistance to treatment processes in water and wastewater treatment plants, higher frequency of both adenoviruses and PMMoV genomes as candidate viral indices in treated sewage and drinking water was observed. The problem of having a viral genome as indices of viral pollution is that it does not express the recent viral pollution because of the longer survivability of the viral genome than the infectious units in water and wastewater. Both infectious adenovirus and infectious phiX174 bacteriophage virus showed similar efficiencies as indices for viral pollution in drinking water and treated sewage samples. On the other hand, qualitative detection of infectious PMMoV failed to express efficiently the presence/absence of infectious enteric viruses in drinking water samples. Infectious adenoviruses and infectious bacteriophage phiX174 virus may be better candidates than adenoviruses genome, polyomaviruses genome, and PMMoV genome and infectivity as viral indices for water and wastewater.

Disinfection of corona and myriad viruses in water by non-thermal plasma: a review.

Nowadays, in parallel to the appearance of the COVID-19 virus, the risk of viruses in water increases leading to the necessity of developing novel disinfection methods. This review focuses on the route of virus contamination in water and introduces non-thermal plasma technology as a promising method for the inactivation of viruses. Effects of essential parameters affecting the non-thermal discharge for viral inactivation have been exposed. The review has also illustrated a critical discussion of this technology with other advanced oxidation processes. Additionally, the inactivation mechanisms have also been detailed based on reactive oxygen and nitrogen species.

Fabrication of SnO2-Sb reactive membrane electrodes for high-efficiency electrochemical inactivation of bacteria and viruses in water

Exposure to waterborne pathogens is still a widespread threat to public health, and efficient and reliable disinfection technologies are urgently needed for decentralized applications. Herein, we developed a novel freestanding and flow-through SnO2-Sb reactive membrane electrode (RME) for electrochemical wastewater disinfection. When water was forced to flow through the porous RME, large amounts of reactive ·OH and H+ were generated within the interior pores of the anode, creating a strongly acidic local environment enriched with ·OH for the rapid inactivation of bacteria and viruses. At an applied voltage of 3.5 V, 100% removal of Escherichia coli (>6.3-log inactivation) was achieved by the flow-through RME at a high flux, which was significantly more effective than the system operated in the conventional flow-by mode (2.7-log inactivation). Using the bacteriophage MS2 strain as a model virus, a disinfection efficiency of 100% (>8.3-log inactivation) was achieved by the RME at 3.5 V. The transmission electron microscopy analysis revealed that E. coli and MS2 in the disinfected water suffered from serious destruction and disintegration, reflecting the strong electrocatalytic oxidation capacity of the charged RME. The SnO2-Sb RME-based electrochemical system performed very well in disinfecting complex municipal wastewater, demonstrating its potential for practical applications.

Photoelectrocatalytic degradation of pharmaceuticals and inactivation of viruses in water with tungsten oxide electrodes

Electrochemically assisted photocatalysis (EAP) is one approach to overcome the fast recombination rates in photocatalysis and increase the quantum efficiency to produce ROS. In comparison to TiO2, tungsten trioxide (WO3) can utilize UV and visible photons and with EAP the external bias can be used to drive the reduction pathway. In this work WO3 electrodes were prepared hydrothermally on FTO. Vertically grown WO3 nanoplate-like structures were thoroughly characterized. The WO3 photoanodes improved photocurrent response compared to P25 and a visible response was measured. These results were attributed to smaller charge transfer resistance and their morphology. The activity of the photoanodes was assessed on the EAP degradation of sulfamethoxazole and MS2 bacteriophage. WO3 yielded ten times higher degradation rates for sulfamethoxazole (2.21 · 10−6 mmol cm−2 min−1) compared to P25. WO3 also yielded the fastest MS2 inactivation rate. A rapid 5-log removal was achieved in 6 min with WO3 that maintained activity over 5 cycles.

Separation and purification of enveloped and non-enveloped viruses from water samples using an aqueous two-phase system

In this study, a new strategy for enriching viruses in water was developed to improve the detection of viruses in environmental samples. The virus was enriched from water by aqueous two-phase system (ATPS), and the recovery and purification were characterized by tissue culture median infection dose (TCID50) and total protein removal rate. The isolation and purification methods of envelope virus (H1N1) and non-envelope virus (human adenovirus type 5, HAdV-5E) were established and optimized. The results of ATPS were compared with those of membrane filtration, polyethylene glycol precipitation and ultrafiltration. Using ATPS, both viruses were enriched in interphase due to the combined action of volume exclusion and bottom stage salting out. Under the optimum conditions, the recoveries of H1N1 and HAdV-5E were 94.87 ± 2.37% and 96.22 ± 4.71% respectively, and the total protein removal rates were 43.02 ± 5.21% and 71.01 ± 6.34% respectively. Compared with conventional methods, ATPS showed superior performance in recovering virus content and water volume, and the average recoveries were 94.06% (H1N1) and 90.07% (HAdV-5E). Therefore, ATPS had superiorities of high recovery, simple operation and maintaining virus particle activity(Fig. 1).

Evaluation of the suitability of pepper mild mottle virus (PMMoV) as an indicator virus for water safety and quality

Wastewater pollution is one of the main causes of waterborne diseases (e.g., diarrheal diseases) because wastewater commonly contains a wide range of pathogenic microorganisms, notably human enteric viruses. Monitoring multiple pathogenic viruses in waters simultaneously is impractical and expensive, so monitoring through virus indicators is essential to ensure water safety and quality. Recently, pepper mild mottle virus (PMMoV) was found as one of the most prevalent viruses in the human gut microbiota and consistently present at high concentrations in human feces and domestic wastewater. This study reviewed the latest information on the presence of PMMoV and human enteric viruses in water environments and in wastewater (water) treatment systems to evaluate the suitability of PMMoV as an indicator virus for water safety and quality. PMMoV was present in all types of waters (e.g., wastewater, surface water, groundwater, coastal water and drinking water) in greater prevalence than human enteric viruses. PMMoV was also removed less or similar to human enteric viruses in various wastewater (water) treatment systems (including disinfection treatment). These results suggest that PMMoV can be used as a suitable indicator virus for 1) assessment of water quality polluted by domestic wastewater; 2) assessment of virus removal efficiency in drinking water treatment plants and 3) assessment of viral safety for drinking water.

Concentration and quantification of Tilapia tilapinevirus from water using a simple iron flocculation coupled with probe-based RT-qPCR.

BackgroundTilapia tilapinevirus, also known as tilapia lake virus (TiLV), is a significant virus that is responsible for the die-off of farmed tilapia across the globe. The detection and quantification of the virus using environmental RNA (eRNA) from pond water samples represents a potentially non-invasive and routine strategy for monitoring pathogens and early disease forecasting in aquaculture systems.MethodsHere, we report a simple iron flocculation method for concentrating viruses in water, together with a newly-developed hydrolysis probe quantitative RT-qPCR method for the detection and quantification of TiLV.ResultsThe RT-qPCR method designed to target a conserved region of the TiLV genome segment 9 has a detection limit of 10 viral copies per µL of template. The method had a 100% analytical specificity and sensitivity for TiLV. The optimized iron flocculation method was able to recover 16.11 ± 3.3% of the virus from water samples spiked with viral cultures. Tilapia and water samples were collected for use in the detection and quantification of TiLV disease during outbreaks in an open-caged river farming system and two earthen fish farms. TiLV was detected from both clinically sick and asymptomatic fish. Most importantly, the virus was successfully detected from water samples collected from different locations in the affected farms (i.e., river water samples from affected cages (8.50 × 103 to 2.79 × 105 copies/L) and fish-rearing water samples, sewage, and reservoir (4.29 × 103 to 3.53 × 104 copies/L)). By contrast, TiLV was not detected in fish or water samples collected from two farms that had previously experienced TiLV outbreaks and from one farm that had never experienced a TiLV outbreak. In summary, this study suggests that the eRNA detection system using iron flocculation, coupled with probe based-RT-qPCR, is feasible for use in the concentration and quantification of TiLV from water. This approach may be useful for the non-invasive monitoring of TiLV in tilapia aquaculture systems and may support evidence-based decisions on biosecurity interventions needed.

Identification coronavirus (SARS-CoV-2) and physicochemical qualities in various water sources and the efficiency of water treatment plants in their removal- case study: Northwest region of Iran

The presence of SARS-CoV-2 virus in water resources and the transmission of diseases caused by it is one of the factors threatening the quality of water resources. This study for the first time concentrates on the presence of SARS-CoV-2 in water resources an urban location. In the present study, the samples were collected from known depth (30–50 cm) of rivers, dams and lakes. In each sample of water collected, different parameters such as residual chlorine, pH (phenol red), turbidity, total dissolved solids and temperature were also measured. Out of 267 samples, two samples were detected to be positive which their Ct values were 34.2 and 35.67. The existence of viable form of this virus in water and wastewater may be associated with issues for providing public health and difficulties in implementation of pandemic control strategies, and this situation can be exacerbated in developing countries that do not have adequate access to sanitation and safe water.

A Review on The Potential Threat of contacting COVID 19 Disease in Drinking Water

The emergence of the pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-COV-2) has generated a lot of attention globally and forced the world to come to its knees through its sporadic spread and eventual increase in the number of infected persons and mortality. However, many means of infection have been described but little is said about any prospective spread through water, since water is a vital means of life support for all. So it is of great importance to scrutinize if it is possible for the COVID19 virus to be spread through water and what can be done to stay protected from the COVID19 virus should there be a possibility of waterborne spread of the coronavirus. A quick review of the virus, its pathogenicity tendencies and what can be done to inactivate the virus in water before being consumed was done vis-?-vis the intervention of suspended sediment load present in water.

The role of pipe biofilms on dissemination of viral pathogens and virulence factor genes in a full-scale drinking water supply system

Water is an important medium for virus transmission and viral pathogens are increasingly appreciated as a significant water safety issue. However, the effect of pipe biofilms on viral pathogens remains unclear. This research aimed to investigate the dissemination of viruses in a full-scale drinking water supply system (DWSS) and the effect of pipe biofilms on viral pathogens in bulking water. Viral pathogens, pathogenic viral hosts, and viral virulence factors (VFs) were found to disseminate from source water to tap water. The proportion of virus and viral VFs in the biofilm was far less than that in water. The contribution of biofilms in pipe wall to viruses and viral VFs in bulking water was less than 4%, and viruses in the biofilm had no obvious effect on pathogenic viruses in water. Dominant viruses carrying VFs changed from Cyanobacteria virus to Mycobacterium virus after advanced water treatment. Mycobacterium and organics were identified as the key factors influencing composition and abundance of viral VFs, which could explain 41.1% of the variation in viral virulence in the water supply system. Host bacteria and organics may be used as the key targets to control the risk of viruses in DWSSs.

Impacts of oxygen and ozone nanobubbles on bacteriophage in aquaculture system

Injection of ozone nanobubbles into water reduces bacterial load, improves dissolved oxygen, and modulates the fish innate immune system. Little is known about the effect that nanobubble treatment has on the concentration of viruses in water. This study, investigated the disinfection impact of oxygen and ozone nanobubbles (NB-O2 and NB-O3) on an Aeromonas hydrophila-specific phage, pAh6.2TG, a virus lab model. After 5-, 10- and 15-min treatments with NB-O2, the concentration of phage remained the same, while the same treatment with NB-O3 eradicated 99.99 to 100% of the phage in the water. Since this phage has been shown to control bacterial infections in fish, we further investigated whether NB-O2 improved the adherence of the phage to the body surface of the fish (i.e. skin mucus, and gills) and phage penetration into fish internal organs, specifically the liver. Nile tilapia, Oreochromis niloticus were used as experimental fish in this study. The results indicated that the number of phages adhered to the skin mucus and gills in NB-O2 treatment group was 1.07 to 15.0 times higher than in the untreated control group without gas nanobubbles. The phage uptake into fish liver after NB-O2 treatment increased 1.29 to 4.75 fold compared to untreated control. These findings suggested a plausible application of NB-O2 treatment for improving efficacy of phage therapy in aquaculture. On the other hand, NB-O3 application may be useful for disinfection of harmful viruses in culture water, but the application would need to be omitted during phage treatment. This study provides preliminary information on potential applications of nanobubble technology in aquaculture to reduce viral load in the water.

Photoelectrocatalytic Degradation of Pharmaceuticals and Inactivation of Viruses in Water with Tungsten Oxide Electrodes

Photoelectrocatalytic Degradation of Pharmaceuticals and Inactivation of Viruses in Water with Tungsten Oxide Electrodes

Recent Update on UV Disinfection to Fulfill the Disinfection Credit Value for Enteric Viruses in Water.

Ultraviolet (UV) radiation alone or in combination with other oxidation processes is increasingly being considered for water disinfection because of stringent regulatory requirements for pathogen inactivation. To fulfill this requirement, an appropriate UV dose or fluence (mJ/cm2) is applied to combat enteric viruses in surface or treated water. There is a need for a cumulative review on the effectiveness of current and emerging UV technologies against various types of human enteric viruses. We extracted the kinetics data from 52 selected experimental studies on enteric virus inactivation using low pressure (LP-UV), medium pressure (MP-UV), UV-LED, and advanced oxidation processes (AOPs) and applied a simple linear regression analysis to calculate the range of UV fluence (mJ/cm2) needed for 4-log10 inactivation. The inactivation of adenoviruses with LP-UV, MP-UV, and UV/H2O2 (10 mg/L) required the highest fluence, which ranged from 159 to 337, 45, and 115 mJ/cm2, respectively. By contrast, when using LP-UV, the inactivation of other enteric viruses, such as the Caliciviridae and Picornaviridae family and rotavirus, required fluence that ranged from 19 to 69, 18 to 43, and 38 mJ/cm2, respectively. ssRNA viruses exhibit higher sensitivity to UV radiation than dsRNA and DNA viruses. In general, as an upgrade to LP-UV, MP-UV is a more promising strategy for eliminating enteric viruses compared to AOP involving LP-UV with added H2O2 or TiO2. The UV-LED technology showed potential because a lower UV fluence (at 260 and/or 280 nm wavelength) was required for 4-log10 inactivation compared to that of LP-UV for most strains examined in this critical review. However, more studies evaluating the inactivation of enteric viruses by means of UV-LEDs and UV-AOP are needed to ascertain these observations.

A model to predict the kinetics of direct (endogenous) virus inactivation by sunlight at different latitudes and seasons, based on the equivalent monochromatic wavelength approach

Sunlight plays an important role in the inactivation of pathogenic microorganisms such as bacteria and viruses in water. Here we present a model that is able to predict the kinetics of direct virus inactivation (i.e. inactivation triggered by sunlight absorption by the virion, without the role played by photochemically produced reactive intermediates generated by water-dissolved photosensitizers) on a global scale (from 60 °S to 60 °N latitude) and for the different months of the year. The model is based on the equivalent monochromatic wavelength (EMW) approach that was introduced recently, and which largely simplifies complex polychromatic calculations by approximating them with a monochromatic equation at the proper wavelength, the EMW. The EMW equation was initially established for mid-July conditions at a mid-latitude, and was then extended to different seasons and to the latitude belt where the day-night cycle is always observed throughout the year. By so doing, the first-order rate constant of direct virus photoinactivation can be predicted on a global scale, with the use of a relatively simple equation plus tables of pre-calculated input data, as a function of latitude, month, and key water parameters. The model was here applied to the virus organism phiX174, a somatic phage that is often used as proxy for pathogenic viruses undergoing fast direct inactivation, and for which a wide array of published inactivation data is available. Model predictions are validated by comparison with field data of inactivation of somatic phages by sunlight.

Persistence and occurrence of SARS-CoV-2 in water and wastewater environments: a review of the current literature.

As the world continues to cope with the COVID-19 pandemic, emerging evidence indicates that respiratory transmission may not the only pathway in which the virus can be spread. This review paper aims to summarize current knowledge surrounding possible fecal–oral transmission of SARS-CoV-2. It covers recent evidence of proliferation of SARS-CoV-2 in the gastrointestinal tract, as well as presence and persistence of SARS-CoV-2 in water, and suggested future directions. Research indicates that SARS-CoV-2 can actively replicate in the human gastrointestinal system and can subsequently be shed via feces. Several countries have reported SARS-CoV-2 RNA fractions in wastewater systems, and various factors such as temperature and presence of solids have been shown to affect the survival of the virus in water. The detection of RNA does not guarantee infectivity, as current methods such as RT-qPCR are not yet able to distinguish between infectious and non-infectious particles. More research is needed to determine survival time and potential infectivity, as well as to develop more accurate methods for detection and surveillance.

Mengovirus as Process Control Virus in the Monitoring of Genomic RNA and Infectivity of Enteric Viruses in Water Matrices

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.

Global subtype diversity, spatial distribution patterns, and phylogenetic analysis of avian influenza virus in water.

The current COVID-19 pandemic highlights the need for zoonotic infectious disease surveillance. Avian influenza virus (AIV) poses a significant threat to animal and public health due to its pandemic potential. Virus-contaminated water has been suggested as an important AIV spread mechanism among multiple species. Nevertheless, few studies have characterized the global AIV subtype diversity and distribution in environmental water. Therefore, this study aims to provide an updated descriptive and phylogenetic analysis of AIVs isolated in water samples from high risk-sites for influenza outbreaks (i.e. live bird markets, poultry farms, and wild bird habitats) on a global scale. The descriptive analysis evidenced that 21 subtypes were reported from nine countries between 2003 and 2020. Fourteen AIV subtypes were solely reported from Asian countries. Most of the viral sequences were obtained in China and Bangladesh with 47.44% and 23.93%, respectively. Likewise, the greatest global AIV subtype diversity was observed in China with 12 subtypes. Live bird markets represented the main sampling site for AIV detection in water samples (64.1%), mostly from poultry cage water. Nevertheless, the highest subtype diversity was observed in water samples from wild bird habitats, especially from the Izumi plain and the Dongting Lake located in Japan and China, respectively. Water from drinking poultry troughs evidenced the greatest subtype diversity in live bird markets; meanwhile, environmental water used by ducks had the highest number of different subtypes in poultry farms. Maximum-likelihood phylogenetic trees of hemagglutinin (HA) and neuraminidase (NA) genes showed that some sequences were closely related among different poultry/wild bird-related environments from different geographic origins. Therefore, the results suggest that even though the availability of gene sequences in public-access databases varies greatly among countries, environmental AIV surveillance represents a useful tool to elucidate potential viral diversity in wild and domestic bird populations.

Virological Environmental Analysis

The presence of enteric viruses in water is now a confirmed fact by various epidemiological studies. The viral contamination of the water could strongly influence the human’s health either through the type the water: bathing or drinking water, or indirectly to the contamination of different types of food that come into contact with contaminated water. The virological environmental analysis poses several problems related to the delay with which the samples are taken, the volumes to be analyzed, the methods of concentrations of water and the methods applied for identifying to present viruses. The molecular techniques have greatly simplified the virological analysis for isolation of viruses, although they are methods that require a certain experience in laboratory techniques.

The impact of coronavirus SARS-CoV-2 (COVID-19) in water: potential risks.

This review summarizes research data on SARS-CoV-2 in water environments. A literature survey was conducted using the electronic databases Science Direct, Scopus, and Springer. This complete research included and discussed relevant studies that involve the (1) introduction, (2) definition and features of coronavirus, (2.1) structure and classification, (3) effects on public health, (4) transmission, (5) detection methods, (6) impact of COVID-19 on the water sector (drinking water, cycle water, surface water, wastewater), (6.5) wastewater treatment, and (7) future trends. The results show contamination of clean water sources, and community drinking water is vulnerable. Additionally, there is evidence that sputum, feces, and urine contain SARS-CoV-2, which can maintain its viability in sewage and the urban-rural water cycle to move towards seawater or freshwater; thus, the risk associated with contracting COVID-19 from contact with untreated water or inadequately treated wastewater is high. Moreover, viral loads have been detected in surface water, although the risk is lower for countries that efficiently treat their wastewater. Further investigation is immediately required to determine the persistence and mobility of SARS-CoV-2 in polluted water and sewage as well as the possible potential of disease transmission via drinking water. Conventional wastewater treatment systems have been shown to be effective in removing the virus, which plays an important role in pandemic control. Monitoring of this virus in water is extremely important as it can provide information on the prevalence and distribution of the COVID-19 pandemic in different communities as well as possible infection dynamics to prevent future outbreaks.

Inactivation efficacy and mechanism of pulsed corona discharge plasma on virus in water

The presence of viruses in water is a major risk for human and animal health due to their high resistance to disinfection. Pulsed corona discharge plasma (PCDP) efficiently inactivates bacteria by causing damage to biological macromolecules, but its effect on waterborne virus has not been reported. This study evaluated the inactivation efficacy of PCDP to viruses using spring viremia of carp virus (SVCV) as a model. The results showed that 4-log10 reduction of SVCV infectivity in cells was reached after 120 s treatment, and there was no significant difference in survival of fish infected with SVCV inactivated by PCDP for 240 s or more longer compared to the control fish without virus challenge, thus confirming the feasibility of PCDP to waterborne virus inactivation. Moreover, the high input energy density caused by voltage significantly improved the inactivation efficiency. The further research indicated that reactive species (RS) generated by pulsed corona discharge firstly reacted with phosphoprotein (P) and polymerase complex proteins (L) through penetration into the SVCV virions, and then caused the loss of viral infectivity by damage to genome and other structural proteins. This study has significant implications for waterborne virus removal and development of novel disinfection technologies.