johns background switcher view original image path

Leland David Bushnell and Carl Alfred Brandly isolated the virus that caused the infection in 1933.

The infection of new-born chicks was characterized by gasping and listlessness with high mortality rates of 40–90%. Hawn in 1931 made the first detailed report which described a new respiratory infection of chickens in North Dakota. The earliest reports of a coronavirus infection in animals occurred in the late 1920s, when an acute respiratory infection of domesticated chickens emerged in North America. As of 2020, 45 species are officially recognised. The common name coronavirus is used to refer to any member of the subfamily Orthocoronavirinae. As the number of new species increased, the genus was split into four genera, namely Alphacoronavirus, Betacoronavirus, Deltacoronavirus, and Gammacoronavirus in 2009. The scientific name Coronavirus was accepted as a genus name by the International Committee for the Nomenclature of Viruses (later renamed International Committee on Taxonomy of Viruses) in 1971. This morphology is created by the viral spike peplomers, which are proteins on the surface of the virus. 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. 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. The name was coined by June Almeida and David Tyrrell who first observed and studied human coronaviruses. The name 'coronavirus' is derived from Latin corona, meaning 'crown' or 'wreath', itself a borrowing from Greek κορώνη korṓnē, 'garland, wreath'. 6.4 Coronavirus disease 2019 (COVID-19).6.3 Middle East respiratory syndrome (MERS).6.2 Severe acute respiratory syndrome (SARS).They have characteristic club-shaped spikes that project from their surface, which in electron micrographs create an image reminiscent of the stellar corona, from which their name derives.

The genome size of coronaviruses ranges from approximately 26 to 32 kilobases, one of the largest among RNA viruses. They are enveloped viruses with a positive-sense single-stranded RNA genome and a nucleocapsid of helical symmetry. In cows and pigs they cause diarrhea, while in mice they cause hepatitis and encephalomyelitis.Ĭoronaviruses constitute the subfamily Orthocoronavirinae, in the family Coronaviridae, order Nidovirales and realm Riboviria. Mild illnesses in humans 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, which is causing the ongoing pandemic. In humans and birds, they cause respiratory tract infections that can range from mild to lethal. Coronaviruses are a group of related RNA viruses that cause diseases in mammals and birds.

Johns background switcher view original image path