Molecular screening of blue mussels indicated high mid-summer prevalence of human genogroup II Noroviruses, including the pandemic “GII.4 2012” variants in UK coastal waters during 2013

Abstract

This molecular study is the first report, to the best of our knowledge, on identification of norovirus, NoV GII.4 Sydney 2012 variants, from blue mussels collected from UK coastal waters. Blue mussels (three pooled samples from twelve mussels) collected during the 2013 summer months from UK coastal sites were screened by RT-PCR assays. PCR products of RdRP gene for noroviruses were purified, sequenced and subjected to phylogenetic analysis. All the samples tested positive for NoVs. Sequencing revealed that the NoV partial RdRP gene sequences from two pooled samples clustered with the pandemic “GII.4 Sydney variants” whilst the other pooled sample clustered with the NoV GII.2 variants. This molecular study indicated mussel contamination with pathogenic NoVs even during mid-summer in UK coastal waters which posed potential risk of NoV outbreaks irrespective of season. As the detection of Sydney 2012 NoV from our preliminary study of natural coastal mussels interestingly corroborated with NoV outbreaks in nearby areas during the same period, it emphasizes the importance of environmental surveillance work for forecast of high risk zones of NoV outbreaks.

GII.4 human norovirus and G8P[1] bovine-like rotavirus in oysters (Crassostrea gigas) from Argentina

“…Since large cargo ships discharge thousand cubic meters of ballast waters as they approach to the ports within the Bahía Blanca estuary, circulation of foreign virus strains could be expected in the region. This would be in accordance with results published by Biswas et al, (2018) that reported maritime activities and coastal water contamination from ships and vessels from distant places as a potential cause of water pollution. To demonstrate this hypothesis, further studies should be assessed in order to establish the phylodynamic of this viral strain.…”