FILTRATION OF RECOMBINANT NORWALK VIRUS-PARTICLES AND BACTERIOPHAGE-MS2 IN QUARTZ SAND - IMPORTANCE OF ELECTROSTATIC INTERACTIONS

Norwalk virus is known to be transmitted through groundwater, yet the environmental factors that facilitate its interstitial transport in su bsurface systems are not yet clear. This paper investigates the filtra tion and surface charge of recombinant: Norwalk virus (rNV) particles that ate morphologically and antigenically similar to live Norwalk str ains bur lack nucleic acid and are therefore noninfectious. In contras t to bacteriophage MS2, a common surrogate for waterborne viral pathog ens, the surface charge of rNV particles and their filtration in packe d beds of quartz sand are strongly influenced by pore water pH over th e environmentally important range of pH 5-7. From a mechanistic perspe ctive, these results suggest that the physicochemical filtration of th e Norwalk virus is highly dependent on the nature and magnitude of ele ctrostatic interactions that develop between the virus and filter medi a. Furthermore, because MS2 and the rNV particles differ significantly with respect to their electrostatic properties, MS2 may not mimic the subsurface filtration of Norwalk virus in natural systems.