@article{liu_chien_papafragkou_hsiao_jaykus_moe_2009, title={Persistence of Human Noroviruses on Food Preparation Surfaces and Human Hands}, volume={1}, ISSN={["1867-0342"]}, DOI={10.1007/s12560-009-9019-4}, number={3-4}, journal={FOOD AND ENVIRONMENTAL VIROLOGY}, author={Liu, Pengbo and Chien, Yu-Wen and Papafragkou, Efstathia and Hsiao, Hui-Mien and Jaykus, Lee-Ann and Moe, Christine}, year={2009}, month={Dec}, pages={141–147} }
 @article{papafragkou_plante_mattison_bidawid_karthikeyan_farber_jaykus_2008, title={Rapid and sensitive detection of hepatitis A virus in representative food matrices}, volume={147}, ISSN={["0166-0934"]}, DOI={10.1016/j.jviromet.2007.08.024}, abstractNote={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.}, number={1}, journal={JOURNAL OF VIROLOGICAL METHODS}, author={Papafragkou, Efstathia and Plante, Michelle and Mattison, Kirsten and Bidawid, Sabah and Karthikeyan, Kalavethi and Farber, Jeffrey M. and Jaykus, Lee-Ann}, year={2008}, month={Jan}, pages={177–187} }
 @article{dh d'souza_sair_williams_papafragkou_jean_moore_jaykus_2006, title={Persistence of caliciviruses on enviromnental surfaces and their transfer to food}, volume={108}, ISSN={["1879-3460"]}, DOI={10.1016/j.ijfoodmicro.2005.10.024}, abstractNote={The noroviruses (NoV) are a common cause of human gastroenteritis whose transmission by foodborne routes is well documented. Fecally contaminated surfaces are likely to contribute to this foodborne transmission and to the propagation of viral disease outbreaks. The purpose of this study was to (i) investigate the stability of NoV on various food preparation surfaces; and (ii) evaluate the degree of virus transfer from these surfaces to a model-ready-to-eat (RTE) food. For the virus persistence experiments, stainless steel, formica and ceramic coupons were artificially contaminated with Norwalk virus (NV), the prototype genogroup I NoV; NV RNA; or feline calicivirus (FCV) F9 (a NoV surrogate), stored at ambient temperature for up to 7 d, and periodically assayed for detection. In the transfer experiments, stainless steel coupons were inoculated with NV or FCV F9 and allowed to dry for 10, 30 and 60 min, after which lettuce leaves were exposed to the surface of the coupons at various contact pressures (10, 100, and 1000 g/9 cm2). Virus recovery was evaluated by RT-PCR (for NV and NV RNA) or by plaque assay (for FCV F9) using Crandell Reese Feline Kidney (CRFK) cells. NV and FCV were detected on all three surfaces for up to 7 d post-inoculation; for FCV, there was an approximate 6 to 7-log10 drop in virus titer over the 7 d evaluation period. By contrast, when stainless steel was inoculated with purified NV RNA, RT-PCR detection was not possible beyond 24 h. Transfer of both NV and FCV from stainless steel surfaces to lettuce occurred with relative ease. This study confirms lengthy NoV persistence on common food preparation surfaces and their ease of transfer, confirming a potential role for environmental contamination in the propagation of viral gastroenteritis.}, number={1}, journal={INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY}, author={DH D'Souza and Sair, A and Williams, K and Papafragkou, E and Jean, J and Moore, C and Jaykus, L}, year={2006}, month={Apr}, pages={84–91} }
 @article{cannon_papafragkou_park_osborne_jaykus_vinje_2006, title={Surrogates for the study of norovirus stability and inactivation in the environment: A comparison of murine norovirus and feline calicivirus}, volume={69}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028X-69.11.2761}, abstractNote={Human noroviruses (NoVs) are the leading cause of food- and waterborne outbreaks of acute nonbacterial gastroenteritis worldwide. As a result of the lack of a mammalian cell culture model for these viruses, studies on persistence, inactivation, and transmission have been limited to cultivable viruses, including feline calicivirus (FCV). Recently, reports of the successful cell culture of murine norovirus 1 (MNV-1) have provided investigators with an alternative surrogate for human NoVs. In this study, we compared the inactivation profiles of MNV-1 to FCV in an effort to establish the relevance of MNV-1 as a surrogate virus. Specifically, we evaluated (i) stability upon exposure to pH extremes; (ii) stability upon exposure to organic solvents; (iii) thermal inactivation; and (iv) surface persistence under wet and dry conditions. MNV-1 was stable across the entire pH range tested (pH 2 to 10) with less than 1 log reduction in infectivity at pH 2, whereas FCV was inactivated rapidly at pH values < 3 and > 9. FCV was more stable than MNV-1 at 56 degrees C, but both viruses exhibited similar inactivation at 63 and 72 degrees C. Long-term persistence of both viruses suspended in a fecal matrix and inoculated onto stainless steel coupons were similar at 4 degrees C, but at room temperature in solution, MNV-1 was more stable than FCV. The genetic relatedness of MNV-1 to human NoVs combined with its ability to survive under gastric pH levels makes this virus a promising and relevant surrogate for studying environmental survival of human NoVs.}, number={11}, journal={JOURNAL OF FOOD PROTECTION}, author={Cannon, Jennifer L. and Papafragkou, Efstathia and Park, Geunwoo W. and Osborne, Jason and Jaykus, Lee-Ann and Vinje, Jan}, year={2006}, month={Nov}, pages={2761–2765} }