Monitoring the marine environment for Small Round Structured Viruses (SRSVS): A new approach to combating the transmission of these viruses by molluscan shellfish

• Published in: Water science and technology 1998-01, Vol.38 (12), p.51-56
• Main Authors: Henshilwood, K., Green, J., Lees, D.N.
• Format: Article
• Language: English
• Subjects: Animal aquaculture; Animal productions; Biological and medical sciences; Cloning; Contamination; Disease transmission; DNA; Environmental monitoring; Fundamental and applied biological sciences. Psychology; gastroenteritis; Harvesting; Invertebrate aquaculture; Marine; Marine environment; Marine molluscs; Microbiological strains; Microbiology; Mollusca; Mollusks; Nucleotide sequence; Outbreaks; Oysters; PCR; Polymerase chain reaction; Public health; Shellfish; Shellfish fisheries; Small round-structured virus; SRSVs; Strains (organisms); Techniques used in virology; Virology; Viruses; Winter
• ISSN: 0273-1223; 1996-9732
• DOI: 10.1016/S0273-1223(98)00799-9

This study investigates human enteric virus contamination of a shellfish harvesting area. Samples were analysed over a 14-month period for Small Round Structured Viruses (SRSVs) using a previously developed nested RT-PCR. A clear seasonal difference was observed with the largest numbers of positive samples obtained during the winter period (October to March). This data concurs with the known winter association of gastroenteric illness due to oyster consumption in the UK and also with the majority of the outbreaks associated with shellfish harvested from this area during the study period. RT-PCR positive amplicons were further characterised by cloning and sequencing. Sequence analysis of the positive samples identified eleven SRSV strains, of both Genogroup I and Genogroup II, occurring throughout the study period. Many shellfish samples contained a mixture of strains with a few samples containing up to three different strains with both Genogroups represented. The observed common occurrence of strain mixtures may have implications for the role of shellfish as a vector for dissemination of SRSV strains. These results show that nested RT-PCR can identify SRSV contamination in shellfish harvesting areas. Virus monitoring of shellfish harvesting areas by specialist laboratories using RT-PCR is a possible approach to combating the transmission of SRSVs by molluscan shellfish and could potentially offer significantly enhanced levels of public health protection.