EC Microbiology

Hepatitis A virus and noroviruses are responsible for viral gastro-enteritis and hepatitis reported worldwide. As contaminated food and water are often the agents for transmitting these viruses, the request for analysis of Hepatitis A virus and Noroviruses in food has progressively increased in recent years. However, detection and/or quantification of low concentrations of these viruses in food matrices is usually complex, even if false negative or false positive results can have significant public health and economic consequences. This paper analyzes results obtained by laboratories participating in a proficiency test for the detection of Noroviruses GI and GII and Hepatitis A virus on artificially contaminated strawberries. Obtained data are encouraging as negative samples are correctly detected by the main participants and few false positive results were observed, above all on the samples slightly contaminated. The best results were observed on samples spiked with a high concentration of Hepatitis A. These data highlight that laboratories’ specificity (the ability of the laboratory to find negative test samples in the absence of the analyte) is good but participants’ sensitivity (the ability of the laboratory to find positive test samples in the presence of the analyte) is questionable.

 Keywords: Proficiency-Testing Schemes; Food Virology; Noroviruses; Hepatitis A; Quality Control; Laboratory Performance

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