Genetic grouping and geographic distribution of Piscine orthoreovirus-1 (PRV-1) in farmed Atlantic salmon in Norway

• Main Authors: Vatne, Nina A., Stormoen, Marit, Lund, Morten, Devold, Magnus, Rimstad, Espen, Wessel, Øystein
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: figshare 2021
• Subjects: Molecular Biology; Evolutionary Biology; FOS Biological sciences; 59999 Environmental Sciences not elsewhere classified; FOS Earth and related environmental sciences; Ecology; Sociology; FOS Sociology; Immunology; FOS Clinical medicine; 69999 Biological Sciences not elsewhere classified; 110309 Infectious Diseases; FOS Health sciences; 60506 Virology; Norway; Atlantic salmon; Salmo salar
• Online Access: https://dx.doi.org/10.6084/m9.figshare.c.5663544.v1; https://springernature.figshare.com/collections/Genetic_grouping_and_geographic_distribution_of_Piscine_orthoreovirus-1_PRV-1_in_farmed_Atlantic_salmon_in_Norway/5663544/1

Abstract Piscine orthoreovirus-1 (PRV-1) is the causative agent of heart and skeletal muscle inflammation (HSMI) in farmed Atlantic salmon (Salmo salar). However, it has been shown that PRV-1 variants differ in their ability to induce HSMI. The objective of this work was to identify the PRV-1 variants in Norwegian aquaculture and their geographical distribution. Sequencing and subsequent analysis of the five genomic segments (S1, S4, M2, L1 and L2) putatively linked to virulence, made out the basis of the study. Thirty-seven Norwegian PRV-1 isolates were sequenced, and they grouped into eight genogroups based on combinations of the five analyzed genomic segments. Two groups were defined as high-virulent and two low-virulent, based on comparison with PRV-1 reference isolates with known virulence. The remaining four groups were of unknown virulence. The geographic distribution indicated a higher frequency of the high-virulent isolates in the mid- and northern regions. The present study confirms circulation of both high- and low-virulent isolates of PRV-1 in farmed Atlantic salmon in Norway. To reduce the impact of PRV-1 related disease, detection and differentiation between high- and low-virulent genogroups of PRV-1 could be a targeted approach for reduction of high-virulent variants.