Real-time PCR and Other Molecular Detection Methods for Food-borne Pathogenic viruses

Resumen

Analysis of foodstuffs for virus contamination requires profoundly sensitive and accurate methods, due to the potentially low number of viruses and the complexity of the sample matrix. In view of these criteria, the polymerase chain reaction is the assay type of choice, with its speed being another useful factor. Real-time PCR (qPCR) is superseding conventional PCR in several areas of molecular diagnostics, and a large variety of published qPCR-based methods for food-borne pathogen detection is available in the scientific literature. In common with other molecular-based methods, qPCR-based analysis of foodstuffs for viruses requires effective controls to ensure that issues associated with low virus numbers and the complexity of the matrix do not result in false negative or positive interpretations of results. These controls are essential for implementation of qPCR-based methods for food-borne virus detection, but in most cases are not included in those which have been published hitherto. Alternative molecular techniques, such as nucleic acid sequence-based amplification (NASBA) and loop-mediated amplification (LAMP) are also suitable for utilization in detection methods for viruses in foods, the same requirements regarding controls pertaining. All molecular-based methods for food-borne virus detection must of necessity contain sample treatment procedures to extract the virus or its nucleic acid out of the food matrix, and these procedures can be elaborate due to matrix complexity. Nonetheless efficient sample treatment methods have been devised, and in combination with molecular assays effective methods for virus analysis are now available for foods. Implementation of these methods in routine diagnostics will support food safety management programmes and assist in outbreak investigation, and help to ensure a safe food supply.