title: Rapid and sensitive detection of hepatitis A virus in representative food matrices.
abstract: Hepatitis A virus (HAV) is an important cause of foodborne disease worldwide. The detection of this virus in naturally contaminated food products is complicated by the absence of a reliable culture method, low levels of contamination, and the presence of matrix-associated compounds which inhibit molecular detection. In this study, we report a novel method to concentrate HAV from foods prior to the application of reverse transcription-PCR (RT-PCR) for detection. Specifically, we used cationically charged magnetic particles with an automated capture system (Pathatrix) to concentrate the virus from 25 g samples of artificially contaminated lettuce, strawberries, green onions, deli-turkey, oysters, and cake with frosting. Detection limits varied according to the product but in most cases, the virus could be consistently detected at input levels corresponding to 10(2)PFU/25 g food sample. For some products, detection was possible at levels as low as 10(-1)PFU/25 g. The assay was applied by a second independent laboratory and was also used to confirm viral contamination of produce items associated with a recent HAV outbreak. Parallel infectivity assays demonstrated that the cationically charged particles bound approximately 50% of the input virus. This is the first application of the automated magnetic capture technology to the concentration of viruses from foods, and it offers promise for facilitating the rapid detection of HAV from naturally contaminated products.
authors.affiliation: Department of Food Science, North Carolina State University, Raleigh, NC 27695-7624, USA.
authors.forename: Efstathia
authors.initials: E
authors.lastname: Papafragkou
authors.forename: Michelle
authors.initials: M
authors.lastname: Plante
authors.forename: Kirsten
authors.initials: K
authors.lastname: Mattison
authors.forename: Sabah
authors.initials: S
authors.lastname: Bidawid
authors.forename: Kalavethi
authors.initials: K
authors.lastname: Karthikeyan
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Farber
authors.forename: Lee-Ann
authors.initials: LA
authors.lastname: Jaykus
mesh_terms: D000818:Animals; D002460:Cell Line; D004196:Disease Outbreaks; D005502:Food / Q000821:virology*; D006506:Hepatitis A / Q000453:epidemiology; D030041:Hepatitis A virus / Q000302:isolation & purification*; D006801:Humans; D008280:Magnetics; D009693:Nucleic Acid Hybridization; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity