The depuration dynamics of oysters (Crassostrea gigas) artificially contaminated with hepatitis A virus and human adenovirus

• Published in: Memórias do Instituto Oswaldo Cruz
• Main Authors: Adriana de Abreu Corrêa, Caroline Rigotto, Vanessa Moresco, Cristian Rafael Kleemann, Adriano Luiz Teixeira, Carlos Rogério Poli, Cláudia Maria Oliveira Simões, Célia Regina Monte Barardi
• Format: Article in Journal/Newspaper
• Language: English
• Published: Fundação Oswaldo Cruz (FIOCRUZ) 2012
• Subjects: aquaculture; depuration; food safety; shellfish; viruses; Microbiology; QR1-502; Infectious and parasitic diseases; RC109-216; Crassostrea gigas
• Online Access: https://doi.org/10.1590/S0074-02762012000100002; https://doaj.org/article/217921f15740417cb971ee9c577109e2

Within the country of Brazil, Santa Catarina is a major shellfish producer. Detection of viral contamination is an important step to ensure production quality and consumer safety during this process. In this study, we used a depuration system and ultraviolet (UV) disinfection to eliminate viral pathogens from artificially infected oysters and analysed the results. Specifically, the oysters were contaminated with hepatitis A virus (HAV) or human adenovirus type 5 (HAdV5). After viral infection, the oysters were placed into a depuration tank and harvested after 48, 72 and 96 h. After sampling, various oyster tissues were dissected and homogenised and the viruses were eluted with alkaline conditions and precipitated with polyethylene glycol. The oyster samples were evaluated by cell culture methods, as well as polymerase chain reaction (PCR) and quantitative-PCR. Moreover, at the end of the depuration period, the disinfected seawater was collected and analysed by PCR. The molecular assays showed that the HAdV5 genome was present in all of the depuration time samples, while the HAV genome was undetectable after 72 h of depuration. However, viral viability tests (integrated cell culture-PCR and immunofluorescence assay) indicated that both viruses were inactivated with 96 h of seawater recirculation. In conclusion, after 96 h of UV treatment, the depuration system studied in this work purified oysters that were artificially contaminated with HAdV5 and HAV.