Norovirus GI and GII and hepatitis A virus in berries and pomegranate arils in Canada

Abstract

Between 2016 and 2021, the Canadian Food Inspection Agency (CFIA) collected 4218 samples of fresh and frozen berries (blackberries, blueberries, raspberries, strawberries and mixed berries) and pomegranate arils at retail across 11 major cities in Canada and tested these samples for the presence of norovirus GI, norovirus GII and hepatitis A virus RNA. The purpose of this testing was to provide information on the prevalence of these viruses in berries and pomegranate arils on the Canadian marketplace. Of the 926 fresh fruit samples tested, norovirus GI RNA was detected in one raspberry sample and norovirus GII RNA was detected in one strawberry sample. Of the 3292 frozen fruit samples tested, norovirus GI RNA was detected in one blackberry sample, one raspberry sample and one strawberry sample, and norovirus GII RNA was detected in one blueberry sample, three raspberry samples, four strawberry samples, one pomegranate arils sample and one mixed berry sample. None of the fresh or frozen fruit samples tested positive for hepatitis A virus RNA. No statistically significant associations were observed between the prevalence of viral RNA in samples of fresh and frozen fruit, between the prevalence of viral RNA in samples of domestic and imported fruit or between the prevalence of viral RNA in samples of specific fruit types. Overall, the prevalence of norovirus GI and GII RNA together in fresh and frozen fruit samples in Canada was 0.36 %. The results of this study may be used to refine surveillance programs for norovirus and hepatitis A virus in fresh and frozen berries and pomegranate arils, e.g. by adapting the commodities tested and/or the numbers of planned samples to better target these hazards. This information may also be used to inform other Government of Canada approaches to better understand the controls associated norovirus and hepatitis A virus in fresh and frozen berries and pomegranate arils.