Methods of Virus Detection in Foods

Virus hazards from food, water and other contaminated environments

“…Detection of viruses in food and environmental samples is challenging because of the large variety and complexity of samples, the possible heterogeneous distribution of a small number of viruses and the presence of components that may inhibit or interfere with virus detection (Goyal, ). A general flow chart for the analytical process (from sampling to final identification and characterization) for the detection of human enteric viruses is given in Fig.…”

“…As no standard procedure or systematic approach evaluating the adsorption of viruses onto different substrates has yet been developed, it is difficult to draw conclusions about the mechanisms involved in virus adsorption (Jin & Flury, ); consequently, establishing appropriate separation and concentration processes is even more demanding. Whatever the method used, the final concentrate should not be cytotoxic to cell cultures used in infectivity assays and should be free of any inhibitors, which may be co‐extracted or co‐concentrated from environmental samples (Goyal, ). A variety of biological and chemical substances that are present in environmental matter or are used during sample processing have been found to act as inhibitors, including polysaccharides, haeme, phenol and cations (Atmar, ).…”

New approaches in microbial pathogen detection

“…Cell-culture-based assay can differentiate between infectious and non-infectious viruses; nevertheless it is limited and not practical, mainly due to the lack of sensitivity, the long analysis time and the lack of susceptible cell lines for many epidemiologically important enteric viruses (Casas and Sunen, 2001;Verhoef et al , 2008). Even though these assays are commonly used to enumerate levels of viable polioviruses and adenoviruses, they are inadequate for the detection of the two most important foodborne viruses, HAVs and NVs, since neither of these replicate or express themselves effi ciently in cell cultures (Goyal, 2006;Jiang et al , 2004;Koopmans and Duizer, 2004). Thus, HAVs and NVs have been detected conventionally using EM and enzyme-linked immunosorbent assay (ELISA) but even these methods are insensitive, lengthy and expensive (Morales-Rayas et al , 2010).…”

“…The sample preparation procedures for detecting viruses in food typically involve one or more of the following: (i) elution of the virus particles from the food using a variety of buffers and solutions including solutions of glycine and sodium chloride, borate and beef extract, saline and beef extract, and beef extract alone; (ii) extraction with an organic solvent, most commonly with Freon to remove insoluble or poorly soluble organic compounds in the water; (iii) concentration of the viruses using sedimentation by antibody or ligand capture, fl occulation, ultra-centrifugation or precipitation (commonly polyethylene glycol precipitation); and (iv) extraction of viral nucleic acids (there are two main approaches using phenol: chloroform extraction and guanidinium isothiocyanate extraction) (Cook and Rzezutka, 2006;Goyal, 2006;Rodriguez-Lazaro et al , 2007). Various strategies have been proposed to improve the performance of each step over the years.…”

Using functionalized nanoparticles as sensors for rapid monitoring of drinking water quality

“…Efforts to deal with this significant threat are often times handicapped by the lack of effective surveillance systems to rapidly detect pathogenic contamination in the field where it occurs (Goyal 2006). Any method that can be applied to detect pathogens in the field needs to be rapid, cost efficient and easy-to-operate.…”