Sep. 1, 2008 - Aug. 31, 2011Award Number
Center for Produce SafetyAmount Awarded
Cheryl Nickerson, Ph.D.
Arizona State University
Human noroviruses are a leading cause of gastrointestinal illness, and account for approximately 700 million infections per annum worldwide. In the United States, it is estimated that approximately 1 person in 10 to 15 persons contracts norovirus annually. Forty percent of norovirus infections are thought to be foodborne, making norovirus the number one cause of food-borne illness in the United States. Norovirus is a significant problem for the molluscan shellfish industry since wild-caught and aquaculture products are often consumed raw and these bivalves can readily bioconcentrate virus particles contaminating their production areas. For the produce industry, norovirus are a significant issue since this virus and other enteric viruses can be inadvertently sprayed on crops by irrigation with virus contaminated water or spread by workers with unclean hands who tend and harvest the crops. This latter produce issue has become an important one since increasingly produce consumed in the US is imported from developing regions and countries (i.e., Latin America), and virus outbreaks have been associated with these imports. There are several important reasons for developing a practical in vitro replication system for human noroviruses. First, current testing technologies for food safety can only detect the presence of virus and cannot determine if the food sample actually contains infectious virus. The second reason for developing a practical in vitro replication system is that while many current detection technologies are quite sensitive, most do not have sensitivity at the low level of an infectious viral dose (10 to 100 virions). To overcome these limitations, we propose to use our 3D intestinal cultures to develop a robust practical method that can be routinely used by food safety laboratories to a) determine the infectious/noninfectious nature of virus samples, and b) reduce the minimum sensitivity needed for positive virus detection.