[Viruses of bivalve shellfish]

Area of Science:

• Marine biology
• Virology
• Aquaculture pathology

Context:

• Bivalve molluscs, as filter feeders, are susceptible to bioaccumulating viruses from their environment.
• Viral infections have been linked to significant mortalities in commercially important bivalve species.
• Previous studies documented irido-like viruses causing mass mortalities in Portuguese oysters (Crassostrea angulata).

Purpose:

• To review and summarize known viral pathogens affecting bivalve molluscs.
• To highlight the diversity of virus families implicated in bivalve health and disease.
• To underscore the challenges in bivalve virus isolation due to the lack of suitable cell lines.

Summary:

• Bivalves can harbor viruses affecting humans and vertebrates, but also suffer from viral diseases.
• Herpesviruses, retroviruses (linked to disseminated neoplasia), and viruses from families like Papovaviridae, Togaviridae, Reoviridae, Birnaviridae, and Picornaviridae have been identified in various bivalve species.
• Specific examples include irido-like virus infections causing mass mortalities in Portuguese oysters and herpesviruses in oysters, scallops, and clams.

Impact:

• Understanding bivalve viral diseases is crucial for aquaculture sustainability and food safety.
• Identifies knowledge gaps, particularly the need for improved bivalve cell culture techniques for diagnostics.
• Provides a foundation for future research into bivalve virology and disease management strategies.