Bioaccumulation, Retention, and Depuration of Enteric Viruses by Crassostrea virginica and Crassostrea ariakensis Oysters

Abstract

Crassostrea ariakensis oysters are under review for introduction into the Chesapeake Bay. However, the human health implications of the introduction have not been fully addressed. This study evaluated rates of bioaccumulation, retention, and depuration of viruses by Crassostrea virginica and C. ariakensis when the two oyster species were maintained in separate tanks containing synthetic seawater of various salinities (8, 12, or 20 ppt). Oyster bioaccumulation tanks were seeded with 10 3 PFU/ml of hepatitis A virus (HAV), poliovirus, male-specific bacteriophage (MS2), and murine norovirus 1 (MNV-1) and 10 3 PCR units/ml of human norovirus (NoV). After 24 h, depuration commenced as oysters (n ‫؍‬ 255) were placed in pathogen-free seawater under continuous filtration. Oysters (n ‫؍‬ 6) were sampled weekly for 1 month from each tank. Viral RNA was recovered using a modified proteinase K, guanidine, and glassmilk method and analyzed by quantitative reverse transcription-PCR. The odds of C. ariakensis oysters harboring NoV, MNV-1, or HAV were statistically greater than the odds of C. virginica oysters harboring the same viruses (MNV-1 odds ratio [OR], 4.5; P ‫؍‬ 0.01; NoV OR, 8.4; P < 0.001; HAV OR, 11.4; P < 0.001). Unlike C. virginica, C. ariakensis bioaccumulated and retained NoV, MNV-1, and HAV for 1 month at all salinities. Additionally, the odds of an oyster testing positive for NoV was 25.5 times greater (P < 0.001) when the oyster also tested positive for MNV-1. This research helps assess the threat of C. ariakensis as a vehicle for viral pathogens due to the consumption of raw oysters and validates the role for MNV-1 as a surrogate for NoV.

Defecation of Norovirus from the Oyster Crassostrea gigas by Depuration Following Translocation of the Growing Area

“…(Le Guyader et al, 2006;Mcleod et al, 2009aMcleod et al, , 2009bTian et al, 2006;Wang et al, 2008), (Maalouf et al, 2010;Nappier et al, 2008). Provost et al (2011) (hematocytes) (acidic digestion) .…”

“…Provost et al (2011) (hematocytes) (acidic digestion) . feline calicivirus murine norovirus (Mcleod et al, 2009b;Nappier et al, 2008;Provost et al, 2011;Ueki et al, 2007).…”

“…(Lees, 2000;Dore et al, 2010). (Lees, 2000;Nappier et al, 2008;Oh et al, 2012;Polo et al, 2014a). , (Lees, 2000;European Commission, 2004;US FDA, 2014).…”

Bioaccumulation and persistence of faecal bacterial and viral indicators in Mytilus edulis and Crassostrea gigas

“…The biological property of the shellfish tissues influences the pattern of accumulation of different pathogens observed in different shellfish species 16 . Several studies have shown that bioaccumulation of pathogens in shellfish (either experimentally under controlled conditions, or naturally in their growing waters) is dependent on a number of factors; including physiology of the shellfish and/or pathogen, the rate of metabolism in the shellfish, the duration of exposure of the shellfish to the pathogen or its source, the exposure dose, and other factors, such as salinity and temperature, that can also influence the filtration rate in the shellfish 5,12,13 . There appears to be a differential selection process involved in bioaccumulation, based on the size and shape of particles, which is influenced by the bioaccumulation efficiency of the shellfish species as well as the ability of the labial palp and gills to reject or filter certain particles 3,26 .…”

Unit Process Wetlands for Removal of Trace Organic Contaminants and Pathogens from Municipal Wastewater Effluents

“…Bivalves are also capable of ingesting a wide variety of pathogens (Silverman et al, 1995;Graczyk et al, 2003Graczyk et al, , 2006Proakis, 2003;Nappier et al, 2008). Given their ability to efficiently remove particles greater than 0.4 lm in diameter from water, bivalves may filter individual bacteria (0.5-2 lm) and FIG.…”