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Enteric Viruses in Process Water
Process water has been defined as water resulting from washing raw materials, rinsing water, or water used for cooling or transport, which usually accumulates organic matter, including micro-organisms. Process water in the fruit and vegetable sector is highly variable in terms of quality parameters, such as dissolved solids, chemical oxygen demand, and microbiological quality. This fact makes it a challenge to implement a standard treatment fit for all purposes. The occurrence of potentially infectious enteric viruses in PW used by the fresh produce industry is likely possible, and thus, it must be closely examined. Several factors must be considered to address this issue: (i) Relatively low levels of enteric viruses introduced will be randomly distributed into large volumes of water and may not be detectable using protocols indicating small volume collection; (ii) sampling points in commercial facilities are critical for pathogen detection; (iii) molecular-based methods, currently used for enteric virus detection in food cannot discriminate between inactivated and potentially infectious enteric viruses; (iv) organic fresh produce market, limiting the use of sanitizers, has tremendously increased in the last years and the food safety perception of consumers must be assured.
The virological quality of process water (PW) used by the produce industry has received limited attention. As a first step to overcoming technical limitations in monitoring viruses in PW, the analytical performance of ultrafiltration was assessed to concentrate viral particles from 20 L of spiked PW. The selected method used for sample concentration of PW was carefully validated, thus enabling the accurate quantification and estimation of viral titers of human enteric viruses and phages. PW from the produce industry was collected periodically from the washing tanks of commercial facilities. The analysis of coliphages was performed by plaque assay, while the occurrence of enteric viruses and crAssphage was determined by molecular techniques. Significant differences in the physicochemical composition of PW, mostly due to the different nature of fresh produce types and differences in the sanitizer used in commercial operation, were observed. Accumulation of crAssphage and coliphages was observed in PW, but correlation with human enteric viruses was not possible due to the low prevalence of these pathogens in the PW analyzed. The obtained results showed that depending on the type of product washed, the product/water ratio and the residual concentrations of the sanitizers, the prevalence and concentration of bacteriophages changed significantly.
2. Human Enteric Viruses
The entry is from 10.3390/foods10081853
- Bennett, S.D.; Sodha, S.V.; Ayers, T.L.; Lynch, M.F.; Gould, L.H.; Tauxe, R.V. Produce-associated foodborne disease outbreaks, USA, 1998–2013. Epidemiol. Infect. 2018, 146, 1397–1406.
- López-Gálvez, F.; Truchado, P.; Sánchez, G.; Aznar, R.; Gil, M.I.; Allende, A. Occurrence of enteric viruses in reclaimed and surface irrigation water: Relationship with microbiological and physicochemical indicators. J. Appl. Microbiol. 2016, 121, 1180–1188.
- López-Gálvez, F.; Randazzo, W.; Vásquez, A.; Sánchez, G.; Tombini Decol, L.; Aznar, R.; Gil, M.I.; Allende, A. Irrigating lettuce with wastewater effluent: Does disinfection with chlorine dioxide inactivate viruses? J. Environ. Qual. 2018, 47.
- Randazzo, W.; López-Gálvez, F.; Allende, A.; Aznar, R.; Sánchez, G. Evaluation of viability PCR performance for assessing norovirus infectivity in fresh-cut vegetables and irrigation water. Int. J. Food Microbiol. 2016, 229, 1–6.
- Tian, P.; Yang, D.; Shan, L.; Wang, D.; Li, Q.; Gorski, L.; Lee, B.G.; Quiñones, B.; Cooley, M.B. Concurrent detection of human norovirus and bacterial pathogens in water samples from an agricultural region in central California Coast. Front. Microbiol. 2017, 8, 1560.
- Li, M.; Baker, C.A.; Danyluk, M.D.; Belanger, P.; Boelaert, F.; Cressey, P.; Gheorghe, M.; Polkinghorne, B.; Toyofuku, H.; Havelaar, A.H. Identification of biological hazards in produce consumed in industrialized countries: A review. J. Food Prot. 2018, 81, 1171–1186.
- Ashbolt, N.J. Microbial Contamination of Drinking Water and Human Health from Community Water Systems. Curr. Environ. Health Rep. 2015, 2, 95–106.
- U.S. Environmental Protection Agency. National Primary Drinking Water Regulations; EPA: Washington, DC, USA, 2009.
- Suslow, T. Postharvest Chlorination: Basic Properties & Key Points for Effective Distribution; University of California, Agriculture and Natural Resources: St. Davis, CA, USA, 1997.
- Joint FAO/WHO Expert Meeting on Microbiological Risk Assessment (JEMRA) Call for Experts and Data on the Safety and Quality of Water Used in the Production of Fishery and Dairy Products; FAO: Rome, Italy, 2019.
- Kearns, E.A.; Gustafson, R.E.; Castillo, S.M.; Alnughaymishi, H.; Lim, D.V.; Ryser, E.T. Rapid large-volume concentration for increased detection of Escherichia coli O157:H7 and Listeria monocytogenes in lettuce wash water generated at commercial facilities. Food Control 2019, 98, 481–488.
- ISO. ISO 15216-1:2017—Microbiology of the Food Chain—Horizontal Method for Determination of Hepatitis A Virus and Norovirus Using Real-Time RT-PCR—Part 1: Method for Quantification. Available online: https://www.iso.org/standard/65681.html (accessed on 2 June 2021).
- Agulló-Barceló, M.; Galofré, B.; Sala, L.; García-Aljaro, C.; Lucena, F.; Jofre, J. Simultaneous detection of somatic and F-specific coliphages in different settings by Escherichia coli strain CB390. FEMS Microbiol. Lett. 2016, 363, 180.
- McMinn, B.R.; Ashbolt, N.J.; Korajkic, A. Bacteriophages as indicators of faecal pollution and enteric virus removal. Lett. Appl. Microbiol. 2017, 65, 11–26.
- Park, G.W.; Ng, T.F.F.; Freeland, A.L.; Marconi, V.C.; Boom, J.A.; Staat, M.A.; Montmayeur, A.M.; Browne, H.; Narayanan, J.; Payne, D.C.; et al. CrAssphage as a novel tool to detect human fecal contamination on environmental surfaces and hands. Emerg. Infect. Dis. 2020, 26, 1731–1739.