title: Susceptibility of murine norovirus and hepatitis A virus to electron beam irradiation in oysters and quantifying the reduction in potential infection risks.
abstract: Consumption of raw oysters is an exposure route for human norovirus (NoV) and hepatitis A virus (HAV). Therefore, efficient postharvest oyster treatment technology is needed to reduce public health risks. This study evaluated the inactivation of HAV and the NoV research surrogate, murine norovirus-1 (MNV-1), in oysters (Crassostrea virginica) by electron beam (E-beam) irradiation. The reduction of potential infection risks was quantified for E-beam irradiation technology employed on raw oysters at various virus contamination levels. The E-beam dose required to reduce the MNV and HAV titer by 90% (D(10) value) in whole oysters was 4.05 (standard deviations [SD], ±0.63) and 4.83 (SD, ±0.08) kGy, respectively. Microbial risk assessment suggests that if a typical serving of 12 raw oysters was contaminated with 10(5) PFU, a 5-kGy treatment would achieve a 12% reduction (from 4.49 out of 10 persons to 3.95 out of 10 persons) in NoV infection and a 16% reduction (from 9.21 out of 10 persons to 7.76 out of 10 persons) in HAV infections. If the serving size contained only 10(2) PFU of viruses, a 5-kGy treatment would achieve a 26% reduction (2.74 out of 10 persons to 2.03 out of 10 persons) of NoV and 91% reduction (2.1 out of 10 persons to 1.93 out of 100 persons) of HAV infection risks. This study shows that although E-beam processing cannot completely eliminate the risk of viral illness, infection risks can be reduced.
authors.affiliation: National Center for Electron Beam Research, Texas A&M University, College Station, TX, USA.
authors.forename: Chandni
authors.initials: C
authors.lastname: Praveen
authors.forename: Brooke A
authors.initials: BA
authors.lastname: Dancho
authors.forename: David H
authors.initials: DH
authors.lastname: Kingsley
authors.forename: Kevin R
authors.initials: KR
authors.lastname: Calci
authors.forename: Gloria K
authors.initials: GK
authors.lastname: Meade
authors.forename: Kristina D
authors.initials: KD
authors.lastname: Mena
authors.forename: Suresh D
authors.initials: SD
authors.lastname: Pillai
mesh_terms: D000818:Animals; D004307:Dose-Response Relationship, Radiation; D004583:Electrons; D005506:Food Contamination / Q000517:prevention & control*; D005525:Food-Processing Industry / Q000379:methods*; D030041:Hepatitis A virus / Q000528:radiation effects*; D029322:Norovirus / Q000528:radiation effects*; D010125:Ostreidae / Q000821:virology*; D010315:Particle Accelerators; D011874:Radiometry