First detection of Ostreid herpesvirus 1 in wild Crassostrea gigas in Argentina

• Published in: Journal of Invertebrate Pathology
• Main Authors: Barbieri, Elena S., Medina, Cintia D., Vázquez, Nuria, Fiorito, Carla, Martelli, Antonela, Wigdorovitz, Andrés, Schwindt, Evangelina, Morga, Benjamin, Renault, Tristan, Parreño, Viviana, Barón, Pedro J
• Other Authors: Laboratoire de Génétique et Pathologie des Mollusques Marins (LGPMM), Santé, Génétique et Microbiologie des Mollusques (SGMM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: [SDV]Life Sciences [q-bio]; [SDU]Sciences of the Universe [physics]; Pacific; Argentina; Crassostrea gigas
• Online Access: https://hal.science/hal-04202350; https://doi.org/10.1016/j.jip.2019.107222

Ostreid herpesvirus 1 (OsHV-1) is a DNA virus of the genus Ostreavirus (Malacoherpesviridae family, Herpesvirales order). Worldwide, OsHV-1 and its microvariants have been associated with increased mortality of Pacific oysters, Crassostrea gigas. Adult asymptomatic oysters also have shown a high prevalence of viral infection. As a consequence, surveillance is needed to better describe OsHV-1 diversity, pathogenicity, clinical signs, and geographical distribution. We examined Crassostrea gigas sampled in October 2017 from the inner zone of the Bahía Blanca Estuary, Argentina, and found that 8 of 30 specimens (26.7%) presented macroscopic lesions in mantle tissues. Histological analysis revealed abnormal presentation of mantle epithelial cells and connective tissues. Conventional and real-time PCR conducted on the oyster samples revealed 70% to be positive for presence of OsHV-1 DNA. The nucleotide sequence of the amplicon obtained from one sample using the primer pair IA1/IA2 (targeting ORF 42/43) was 99% identical to OsHV-1 reference as well as µVar strains B and A (KY271630, KY242785.1), sequenced from France and Ireland. This finding represents the first detection of OsHV-1 DNA in a wild population of C. gigas in Argentina in association with gross mantle lesions.