Avian Reovirus Pathogenesis and Molecular Characterization

Avian reovirus (ARV) is a non‐enveloped, double‐stranded RNA virus of the Orthoreovirus genus that inflicts considerable economic losses in poultry through arthritis, tenosynovitis, pericarditis and runting‐stunting syndromes. Its segmented genome encodes structural proteins, including the σC attachment protein, and nonstructural factors that subvert host signalling to promote replication. Pathogenesis involves receptor‐mediated entry, activation of cellular kinases and endocytic pathways, followed by cytoplasmic transcription and assembly of progeny virions. Genetic diversity is driven by point mutations, reassortment of genome segments and occasional recombination, yielding multiple genotypic clusters with variable antigenicity. Such evolution underpins vaccine escape and vaccination failure in commercial flocks. Molecular characterisation encompasses genome sequencing, phylogenetic analysis of the σC gene clusters, antigenic mapping of surface proteins and investigation of host–virus interactions at the cellular level. Integrated surveillance and updated vaccine formulations based on locally circulating genotypes are critical for disease control.

Research from Nature Portfolio

Genotypic surveys in California have revealed six distinct ARV clusters circulating in tenosynovitis outbreaks, with the major diversity concentrated in genome segments encoding capsid proteins L3, S1 and M2. Longitudinal sampling demonstrated shifts in cluster representation over time, emphasising ongoing viral adaptation and the limited cross‐protection afforded by legacy vaccine strains. A complementary investigation in Canada characterised emerging arthrogenic ARV variants isolated from broiler tendons, identifying four genotypic groups with pronounced antigenic heterogeneity in the σC surface protein. Antisera against commercial vaccines failed to neutralise these variants, highlighting the necessity of antigenic matching for effective immunisation.

Avian Reovirus Pathogenesis and Molecular Characterization publication trend

The graph below shows the total number of articles in avian reovirus pathogenesis and molecular characterization across all publications each year (not limited to Nature Index journals).

Technical terms

Sigma C protein: Major surface protein of ARV that mediates cell attachment and determines antigenic specificity.

Tenosynovitis: Inflammation of the tendon sheath commonly induced by ARV in poultry, leading to lameness and reduced mobility.

Phylogenetic cluster: Grouping of virus strains based on shared genetic sequences that reflect their evolutionary relationships.

Reassortment: Process by which segmented viruses exchange entire genome segments during co‐infection, generating novel combinations.

Reverse transcriptase polymerase chain reaction (RT-PCR): Diagnostic technique that converts viral RNA into DNA and amplifies specific sequences for detection and typing.

References

1. Genotypic Characterization of Emerging Avian Reovirus Genetic Variants in California. Scientific Reports (2019).
2. Phenotypic, genotypic and antigenic characterization of emerging avian reoviruses isolated from clinical cases of arthritis in broilers in Saskatchewan, Canada. Scientific Reports (2017).
3. Molecular and pathological investigation of avian reovirus (ARV) in Egypt with the assessment of the genetic variability of field strains compared to vaccine strains. Frontiers in Microbiology (2023).
4. A Novel Variant of Avian Reovirus Is Pathogenic to Vaccinated Chickens. Viruses (2023).
5. Cell Entry of Avian Reovirus Modulated by Cell-Surface Annexin A2 and Adhesion G Protein-Coupled Receptor Latrophilin-2 Triggers Src and p38 MAPK Signaling Enhancing Caveolin-1- and Dynamin 2-Dependent Endocytosis. Microbiology Spectrum (2023).