Gourt Home::Gourt :: Coronaviridae
Introduction
Coronaviruses are enveloped, single stranded, positive-sense RNA viruses (27-31kb) with club-shaped surface about 120-160 nm in diameter that resemble a “corona”. Both 5' and 3' ends of the genome have a cap and poly (A) tract respectively. The envelope consists of two viral-specified structural glycoproteins S and M. Glycoprotein S is located on the outer membrane of the envelope and is responsible for the club-shaped projections. On the other hand, glycoprotein M is a transmembrane molecule and is located on the inner part of the envelope. Another important structural protein is the phosphoprotein N which is responsible for the helical symmetry of the nucleocapsid that encloses the genomic RNA.
The Coronaviridae are a family of viruses, including the following genera:
- Genus Coronavirus; type species: Infectious bronchitis virus
- Genus Torovirus; type species: Equine torovirus
Transmission
Coronaviruses are transmitted by faecal-oral route or by aerosols of respiratory secretions and the main cells that are infected are the epithelia cells.
Pathogenesis
Coronaviruses infect a wide range of mammals and birds and occur worldwide. Although, most diseases are mild, sometimes they can cause more severe situations in humans, like for example an infection of the respiratory tract including Severe Acute Respiratory Syndrome (SARS). They can also cause enteric infections in very young infants and in rare situations neurological syndrome.
External links
Nidovirales
"Coronaviridae"