This article is about the group of viruses.
For the disease involved in the ongoing COVID-19 pandemic, see Coronavirus disease
2019. For the virus that causes this disease, see Severe acute respiratory syndrome coronavirus 2. For the upcoming Indian film,
see Coronavirus (film).
Orthocoronavirinae
Transmission electron
micrograph of avian infectious
bronchitis virus
Illustration of the morphology of
coronaviruses; the club-
shaped viral spike peplomers (red)
create the look of a corona
surrounding the virion when seen
with an electron microscope.
Virus classification
(unranked Virus
):
Realm: Riboviria
Kingdom: Orthornavirae
Phylum: Pisuviricota
Class: Pisoniviricetes
Order: Nidovirales
Family: Coronaviridae
Subfamily: Orthocoronavirin
ae
Genera[1]
Alphacoronavirus
Betacoronavirus
Gammacoronavirus
Deltacoronavirus
Synonyms[2][3][4]
Coronavirinae
Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds. In humans,
these viruses cause respiratory tract infections that can range from mild to lethal. Mild illnesses include some cases of the common
cold (which is also caused by other viruses, predominantly rhinoviruses), while more lethal varieties can cause SARS, MERS,
and COVID-19. Symptoms in other species vary: in chickens, they cause an upper respiratory tract disease, while in cows and pigs
they cause diarrhea. There are as yet no vaccines or antiviral drugs to prevent or treat human coronavirus infections.
Coronaviruses constitute the subfamily Orthocoronavirinae, in the family Coronaviridae, order Nidovirales, and realm Riboviria.[5]
[6]
They are enveloped viruses with a positive-sense single-stranded RNA genome and a nucleocapsid of helical symmetry.
[7]
The genome size of coronaviruses ranges from approximately 26 to 32 kilobases, one of the largest among RNA viruses.[8] They
have characteristic club-shaped spikes that project from their surface, which in electron micrographs create an image reminiscent of
the solar corona, from which their name derives.[9]
Contents
1Etymology
2History
3Microbiology
o 3.1Structure
o 3.2Genome
o 3.3Replication cycle
3.3.1Cell entry
3.3.2Genome translation
3.3.3Replicase-transcriptase
3.3.4Assembly and release
o 3.4Transmission
4Classification
5Origin
6Infection in humans
o 6.1Common cold
o 6.2Severe acute respiratory syndrome (SARS)
o 6.3Middle East respiratory syndrome (MERS)
o 6.4Coronavirus disease 2019 (COVID-19)
7Infection in animals
o 7.1Farm animals
o 7.2Domestic pets
o 7.3Laboratory animals
8Prevention and treatment
9See also
10References
11Further reading
Etymology
The name "coronavirus" is derived from Latin corona, meaning "crown" or "wreath", itself a borrowing from Greek κορώνη korṓnē,
"garland, wreath".[10][11] The name was coined by June Almeida and David Tyrrell who first observed and studied human
coronaviruses.[12] The word was first used in print in 1968 by an informal group of virologists in the journal Nature to designate the
new family of viruses.[9] The name refers to the characteristic appearance of virions (the infective form of the virus) by electron
microscopy, which have a fringe of large, bulbous surface projections creating an image reminiscent of the solar corona or halo.[9]
[12]
This morphology is created by the viral spike peplomers, which are proteins on the surface of the virus.[13]
History
