Cardiovirus

Overview

Electron micrograph of Cardiovirus particles

Cardiovirus is a genus of viruses in the family Picornaviridae. This genus includes several species that are known to infect mammals, including humans and rodents. Cardioviruses are non-enveloped, positive-sense single-stranded RNA viruses. They are primarily associated with diseases of the heart and central nervous system.

Structure

Cardioviruses are small, spherical viruses with a diameter of approximately 30 nm. The viral capsid is composed of 60 copies each of four structural proteins: VP1, VP2, VP3, and VP4. The genome of cardioviruses is a single-stranded RNA molecule of about 7,500 nucleotides, which is polyadenylated at the 3' end and has a covalently linked protein, VPg, at the 5' end.

Genome Organization

The genome of cardioviruses is organized into a single open reading frame that encodes a polyprotein. This polyprotein is cleaved by viral proteases into structural and non-structural proteins. The structural proteins form the viral capsid, while the non-structural proteins are involved in viral replication and host cell interaction.

Replication Cycle

Cardioviruses replicate in the cytoplasm of host cells. The replication cycle begins with the attachment of the virus to a host cell receptor, followed by entry into the cell. Once inside, the viral RNA is released and translated into a polyprotein, which is then processed into functional viral proteins. The viral RNA is replicated by the viral RNA-dependent RNA polymerase, and new virions are assembled in the cytoplasm before being released to infect new cells.

Pathogenesis

Cardioviruses are known to cause a range of diseases in their hosts. In humans, they have been associated with myocarditis, encephalitis, and other inflammatory conditions. The exact mechanisms of pathogenesis are not fully understood, but it is believed that the virus can directly damage host tissues and also trigger immune-mediated damage.

Species

The genus Cardiovirus includes several species, such as:

• Encephalomyocarditis virus (EMCV)
• Theiler's murine encephalomyelitis virus (TMEV)

Transmission

Cardioviruses are primarily transmitted via the fecal-oral route, although other routes of transmission, such as respiratory or vector-borne, may also occur. Rodents are considered the primary reservoir hosts for many cardioviruses, and they can spread the virus to other animals, including humans.

Prevention and Control

Currently, there are no specific vaccines or antiviral treatments available for cardiovirus infections. Prevention relies on good hygiene practices, rodent control, and avoiding contact with infected animals.

Related Pages

• Picornaviridae
• RNA virus
• Myocarditis
• Encephalitis