Rethinking the Significance of Reovirus in Water and Wastewater

The genus Orthoreovirus contains nonenveloped viruses with double-stranded gene segments encased in a double-layered icosahedral capsid shell. These features constitute major determinants of virion stability in the environment and virion resistance against physical and chemical agents. Reovirus (ReoV) is the general term most commonly used for all virus strains that infect humans and nonhuman animals. Several studies have demonstrated the frequent occurrence of ReoV in wastewaters and natural waters, including surface and ground waters from different geographical areas. Most of these studies have reported higher concentrations of ReoV than any other enteric virus analyzed. They are more commonly isolated in chlorine-disinfected wastewaters than other enteric viruses, and appear to survive longer in water. The ability of ReoV to form large aggregates, even with different types of enteric viruses (e.g., poliovirus) and their ability to undergo mechanisms of gene segment reassortment among different serotypes may also explain their greater stability. Different approaches have been applied for concentration of ReoV from water; however, the recovery efficiency of the filtration methods has not been fully evaluated. Recently, molecular methods for identification of ReoV strains and quantification of virus genome have been developed. Studies have shown that the overall detection sensitivity of ReoV RNA is enhanced through initial replication of infectious virions in cell culture. More studies are needed to specifically address unresolved issues about the fate and distribution of ReoV in the environment since this virus is not commonly included in virological investigations.     

Resource recovery potential from source-separated organic municipal solid waste: opportunities for organic fertilizer production and creating sustainable urban agriculture in Ethiopia

Journal of Material Cycles and Waste Management - Increasing waste production and its disposal into the environment without treatment and resource recovery is considered as a threat to the...     

Comparison of Multiple Passage Integrated Cell Culture-PCR and Cytopathogenic Effects in Cell Culture for the Assessment of Poliovirus Survival in Water

The goal of this study was to determine if a cytopathogenic effects (CPE) cell culture assay and an integrated cell culture PCR (ICC-PCR) assay would yield similar or different results when used to assess virus survival in water. Poliovirus type 1 was added to dechlorinated tapwater and stored at room temperature (22.5–24°C) for a total of 50 days. Samples were assayed at defined time intervals by the most probable number (MPN) method on Buffalo green monkey kidney cells (BGM) by CPE and additionally by ICC-PCR. Monolayers that were CPE negative on first passage were passed onto fresh monolayers of cells for a second and third time if still negative. By CPE assay, second passage was observed to yield a greater titer (2,300 vs. 24,000 MPN/ml) and third passage also resulted in an increased titer. ICC-PCR proved to be a more rapid and sensitive method than conventional cell culture for determining virus inactivation rates in water. Poliovirus survived in tapwater for up to 32 days, as assessed by both third passage ICC-PCR and CPE. There was no statistical difference in the inactivation rates between the two methods. To determine the total number of infectious viruses, these findings indicate the need for performing three cell culture passages or, alternatively, ICC-PCR on first passage.     

Assessment of the Antiviral Properties of Zeolites Containing Metal Ions

The antiviral properties of zeolite (sodium aluminosilicate) powders amended with metal ions were assessed using human coronavirus 229E, feline infectious peritonitis virus (FIPV), and feline calicivirus F-9. Zeolites containing silver and silver/copper caused significant reductions of coronavirus 229E after 1 h in suspension. The silver/copper combination yielded a >5.13-log₁₀ reduction within 24 h. It was also the most effective (>3.18-log₁₀) against FIPV after 4 h. Other formulations were ineffective against FIPV. On plastic coupons with incorporated silver/copper-zeolites, >1.7-log₁₀ and >3.8-log₁₀ reductions were achieved for coronavirus 229E and feline calicivirus within 24 h, respectively. Silver/copper zeolite reduced titers of all viruses tested, suggesting that it may be effective against related pathogens of interest [i.e., SARS coronavirus, other coronaviruses, human norovirus (calicivirus)]. Of note, it was effective against both enveloped and nonenveloped viruses. Metal-zeolites could therefore possibly be used in applications to reduce virus contamination of fomites and thus the spread of viral diseases.     

Assessment of a Portable Handheld UV Light Device for the Disinfection of Viruses and Bacteria in Water

Effective individual microbiological water purifiers are needed for consumption of untreated water sources by campers, emergency use, military, and in developing counties. A handheld UV light device was tested to assess if it could meet the virus reduction requirements established by the United State Environmental Protection Agency, National Science Foundation and the World Health Organization. The device was found capable of inactivating at least 4 log₁₀ of poliovirus type 1, rotavirus SA-11 and MS-2 virus in 500 mL volumes of general case test water. But in the presence of high turbidity and organic matter, filtration was necessary to achieve a 4 log₁₀ reduction of the test viruses.     

Physicochemical and compositional analyses of household solid wastes: opportunities for bioenergy production and sustainable waste management in Ethiopia

Journal of Material Cycles and Waste Management - This study aimed to determine the quantity and quality of source separated organic household solid waste (SSOHSW) generation in Addis Ababa,...     

Viruses in surface and drinking waters

Over 114 different human enteric viruses are known. They are all excreted into sewage, and opportunities exist for them to find their way into water distribution systems. The characteristics of the illnesses caused by enteric viruses make their transmission by water difficult to recognize. Methods are not available for isolating all of the enteric viruses from water, so that finding any type of human virus in drinking water is an indication that other types may also be present. With improvements in technology, our laboratory has recently been able to detect group B coxsackieviruses, rotaviruses, and hepatitis A virus in chlorinated drinking water. At present, there are no uniform methods for concentrating, isolating, and identifying viruses in water. Emphasis should be placed on seeking uniformity in methods so that standards can be set for viruses in water.     

QUALITY STUDY OF GRAYWATER TREATMENT SYSTEMS1

ABSTRACT: A residential single family dwelling was retrofitted to recycle graywater for landscape irrigation and toilet flushing. The objective of this study was to determine improvements in graywater quality by evaluating five simple graywater treatment systems that were easily adapted to the household plumbing. The treatment systems consisted of (1) water hyacinths and sand filtration, (2) water hyacinths, copper ion disinfection, and sand filtration, (3) copper ion disinfection and sand filtration, (4) copper/silver ion disinfection and sand filtration, and (5) 20–μm cartridge filtration. Water quality parameters measured were fecal and total coliform indicator bacteria, nitrates, suspended solids, and turbidity. Reductions in bacterial concentration, suspended solids and turbidity were achieved by all systems tested. Treatment reduced nitrate concentrations to an average of 2.6 mg/liter. Reductions in suspended solids, and turbidity were influenced more by the quality of the graywater entering the treatment system than the efficiency of the systems themselves. The water hyacinths and sand filtration system provided the best graywater quality in terms of the concentrations of fecal indicator bacteria. The system providing the best water quality in regard to average suspended solids after treatment was the water hyacinths, copper ion, and sand filtration system, and the best average turbidity was achieved by the copper/silver ion generating unit with sand filtration. All systems were capable of significant reductions in fecal indicator bacteria, suspended solids, and turbidity; however, additional treatment or disinfection would be necessary to further reduce the level of coliform and fecal coliform bacteria to achieve regulatory standards in the State of Arizona.     

Nikinake: the mobilization of labour and skill development in rural Ethiopia

A public mobilization approach known as nikinake drives implementation and technology upscaling in Ethiopia's agricultural extension. This study investigates and describes the processes and effectiveness of nikinake as an extension method used for natural resource management (NRM). The paper draws on empirical field research conducted in Oromia and the southern region of Ethiopia by looking at nikinake in the context of a watershed management campaign in 2015 and 2016. Nikinake is used as an approach to mobilize the public and to promote the skills of farmers and development actors. In principle, the implementation of NRM is voluntary; however, it is largely planned top‐down and enforced through state actors and informal institutions. This study suggests effective integration of social mobilization with reliable extension and a paradigm shift in emphasis from spatial coverage to an effective outcome. Additionally, sustainability and scalability of NRM interventions could be ameliorated by improving experts’ technical skills, raising farmers’ awareness, improving an incentive system, building trust, and better integrating past watershed management and future planning activities. We reflect on the significance of the nikinake experience in Ethiopia for a broader theory of extension‐as‐mobilization for rural development. From the Ethiopian case, a more general recommendation emerges for extension‐as‐mobilization schemes. For long‐term development, it is worthwhile to consider the fit between yearly campaigns as ad hoc project organizations and the existing pattern of actors and institutions responsible for rural development.