T4-12 A Simple qRT-PCR Method for Distinguishing Potentially Infectious and Inactivated Norovirus

Monday, July 29, 2013: 4:45 PM
213D (Charlotte Convention Center)
David Kingsley, U.S. Department of Agriculture-ARS-FSIT, Dover, DE
Introduction: Norovirus strains have not been reproducibly replicated in the laboratory and there is no suitable small animal model for evaluating infectivity of this virus.  To date, this has limited the ability to evaluate intervention methods and inactivation protocols. 

 Purpose: Because RT-PCR based methods only detect the presence of norovirus RNA sequences, RT-PCR by itself cannot give much information about whether the amplified nucleotide sequence was originally derived from an infectious or an inactivated virion. 

 Methods: To initiate an infection, the norovirus virion must attach to its host cell via interactions with histo-blood group antigens (HBGAs).  Porcine gastric mucin, which chemically mimics HBGA receptors, can, when linked to magnetic beads, be used to bind and extract virions.

 Results: Results described here, using GI.1 Norovirus (Norwalk strain) show that after ultra-violet light, high pressure, and thermal treatments, the ability of this virus to bind to swine gastric mucin is substantially abrogated.

 Significance: These results indicate that the loss of NoV binding to porcine gastric mucin can be used as a means to preferentially exclude non-infectious virus particles from subsequent RT-PCR detection.