Evaluation of the suitability of a plant virus, pepper mild mottle virus, as a surrogate of human enteric viruses for assessment of the efficacy of coagulation–rapid sand filtration to remove those viruses

Abstract

Here, we evaluated the removal of three representative human enteric viruses - adenovirus (AdV) type 40, coxsackievirus (CV) B5, and hepatitis A virus (HAV) IB - and one surrogate of human caliciviruses - murine norovirus (MNV) type 1 - by coagulation-rapid sand filtration, using water samples from eight water sources for drinking water treatment plants in Japan. The removal ratios of a plant virus (pepper mild mottle virus; PMMoV) and two bacteriophages (MS2 and φX174) were compared with the removal ratios of human enteric viruses to assess the suitability of PMMoV, MS2, and φX174 as surrogates for human enteric viruses. The removal ratios of AdV, CV, HAV, and MNV, evaluated via the real-time polymerase chain reaction (PCR) method, were 0.8-2.5-log when commercially available polyaluminum chloride (PACl, basicity 1.5) and virgin silica sand were used as the coagulant and filter medium, respectively. The type of coagulant affected the virus removal efficiency, but the age of silica sand used in the rapid sand filtration did not. Coagulation-rapid sand filtration with non-sulfated, high-basicity PACls (basicity 2.1 or 2.5) removed viruses more efficiently than the other aluminum-based coagulants. The removal ratios of MS2 were sometimes higher than those of the three human enteric viruses and MNV, whereas the removal ratios of φX174 tended to be smaller than those of the three human enteric viruses and MNV. In contrast, the removal ratios of PMMoV were similar to and strongly correlated with those of the three human enteric viruses and MNV. Thus, PMMoV appears to be a suitable surrogate for human enteric viruses for the assessment of the efficacy of coagulation-rapid sand filtration to remove viruses.

Pepper mild mottle virus as a water quality indicator

“…40 This unique feature of PMMoV in terms of environmental stability supports its usefulness as a performance indicator in water and wastewater treatment plants to evaluate treatment efficiency, as suggested for wastewater reclamation systems 31 and coagulation-RSF. 47 The application of PMMoV as a performance indicator can be extended to other treatment processes, such as membrane filtration and disinfection, although more research is necessary in the case of the latter to determine if reductions of PMMoV by different disinfection methods are relatable to that of enteric viruses.…”

Pepper mild mottle virus: A plant pathogen with a greater purpose in (waste)water treatment development and public health management

“…published their study in 2006, other metagenomic studies have verified the abundance of PMMoV in human feces (Moore et al, 2015, Nakamura et al, 2009, Victoria et al, 2009), untreated domestic wastewater (Wang et al, 2018), tertiary-treated domestic wastewater (Rosario et al, 2009a), and even indoor air filters (Rosario et al, 2018). Additionally, PMMoV has been incorporated in over 29 peer-reviewed and published investigations related to microbial water and food quality as well as (waste)water treatment technologies throughout the world (Ahmed et al, 2018, Asami et al, 2016, Betancourt et al, 2014, Fout et al, 2017, Gu et al, 2018, Hamza et al, 2011, Han et al, 2014, Haramoto et al, 2013, Hruby et al, 2013, Hughes et al, 2017, Kato et al, 2018, Kitajima et al, 2014, Kuroda et al, 2015, Lee et al, 2017, Rachmadi et al, 2015, Rosiles-González et al, 2017, Saeidi et al, 2018, Sangsanont et al, 2016, Sassi et al, 2018, Schmitz et al, 2016, Shirasaki et al, 2017, Shirasaki et al, 2018, Shrestha et al, 2018, Symonds et al, 2015, Symonds et al, 2016, Symonds et al, 2014, Symonds et al, 2017, Tandukar et al, 2018, Verbyla et al, 2016, Wang et al, 2018). The main purpose of this review is to consolidate the available information from a variety of different disciplines to understand how and when PMMoV can best be used as an enteric virus surrogate and/or domestic wastewater marker (Figure 1).…”

Where do we stand to oversee the coronaviruses in aqueous and aerosol environment? Characteristics of transmission and possible curb strategies

“…The effect of precipitation and filtration on virus removal highly depends on the filtration technologies. The effect of membrane filtration on virus elimination is better than trickle filtration and sand filtration [124] , [125] . The reverse osmosis (RO) process should be the best in theory for virus removal, but in practice, more ultrafiltration (UF) and nanofiltration (NF) membranes are adopted due to more cost-effective reason and similar removal level to be obtained (over 4 log units reduction for norovirus) [125] , [126] .…”