reovir

Reoviridae is a family of double-stranded RNA viruses that infect a wide range of hosts, including humans, animals, and plants. The name "reovirus" is derived from the original classification as *respiratory enteric orphan viruses*, reflecting their initial discovery in association with respiratory and gastrointestinal diseases in humans and animals. However, many reoviruses are not associated with disease in their natural hosts and are considered non-pathogenic.

Reoviruses have a characteristic icosahedral capsid structure with a segmented genome, typically consisting of 10–12 double-stranded RNA segments. These segments encode structural and non-structural proteins essential for viral replication and assembly. The viral particles are non-enveloped, meaning they lack a lipid bilayer, which contributes to their stability in the environment.

Human reovirus type 3 (HRV-3) is the most well-studied member of the family, often used as a model organism in virology research due to its well-characterized life cycle and lack of pathogenicity in humans. Reoviruses replicate in the cytoplasm of host cells, utilizing host machinery to transcribe and translate their segmented genome. The viral replication process involves several stages, including attachment to cell receptors, penetration, uncoating, transcription, translation, replication of viral RNA, and assembly of new virions.

Reoviruses are classified into several genera, including *Orthoreovirus*, *Phytoreovirus*, *Aquareovirus*, and *Orthoreovirus*-like viruses. *Orthoreovirus* is the most clinically relevant genus, containing viruses that infect mammals and birds. Some reoviruses, such as those in the *Phytoreovirus* genus, are significant plant pathogens, causing diseases in crops like wheat and maize.

Reoviruses are generally stable in the environment due to their robust capsid structure, resisting heat, acid, and detergents. This stability contributes to their persistence and potential for transmission. While most reoviruses are not associated with severe disease, they have been studied for their potential as oncolytic agents—viruses that selectively infect and kill cancer cells—due to their ability to induce apoptosis in certain tumor cells. Additionally, reoviruses have been explored as vaccine vectors for delivering antigens to the immune system.