The family of Corona viruses comprises a group of large, single, plus-stranded RNA viruses isolated from several species and is previously known to cause common cold and diarrhoea in humans.
In humans, coronaviruses infect cells of the upper respiratory and gastrointestinal tract and are responsible for about one third of all common colds.
The most common coronaviruses affecting people around the world are coronaviruses 229E, NL63, OC43, and HKU1. SARS and MERS are less common. SARS= Severe Acute Respiratory Syndrome MERS= Middle East Respiratory Syndrome
The coronavirus affecting people in 2020 is 2019-nCoV; its outbreak happened in the Chinese city of Wuhan.
The coronavirus 2019-nCoV appears to have a lower fatality rate than the SARS virus, but it is considered dangerous as it spreads much quicker than other coronaviruses.
The first complete genome sequence of the coronavirus 2019-nCoV was done on January 29, 2020, in The Pasteur Institute, France.
Coronavirus 2019-nCoV does not need any mutation to adapt and spread across various geographies, which is the reason for its fast spread.
The phylogenetic tree showed that 2019.nCoV significantly clustered with Bat SARS-like Coronavirus sequence isolated in 2015, indicating that the virus was transmitted from bats or another host.
A mutation in the coronavirus Nucleocapsid and the Spike Glycoprotein, conferred upon it the ability to infect humans.