Detection and quantification of noroviruses in shellfish

Area of Science:

• Food Safety
• Virology
• Molecular Diagnostics

Background:

• Noroviruses (NoVs) are a leading cause of acute gastroenteritis globally.
• High environmental discharge of resistant NoVs leads to food contamination, particularly in shellfish.
• Accurate NoV detection in shellfish is hindered by low viral loads, extraction difficulties, inhibitors, and genetic diversity.

Purpose of the Study:

• To adapt a commercial kit for efficient Norovirus detection in shellfish.
• To implement a one-step real-time RT-PCR with an external viral control.
• To enhance the reliability and quality assurance of NoV quantification in oyster samples.

Main Methods:

• Adaptation of a commercial kit for Norovirus detection.
• Utilized a one-step real-time reverse transcription-PCR (RT-PCR) assay.
• Incorporated an external viral control and magnetic silica for inhibitor removal.

Main Results:

• The adapted method reproducibly detected similar Norovirus levels compared to a previous method in oysters.
• Validation studies showed good correlation between methods, with variability linked to contamination levels.
• Magnetic silica effectively removed inhibitors, enhancing assay performance.

Conclusions:

• The optimized real-time RT-PCR method provides reliable Norovirus quantification in shellfish.
• Extraction and amplification controls increase confidence in results, crucial for food safety.
• This validated approach supports regulatory evaluation for European food safety standards.