On 31 December 2019, the World Health Organization (WHO) was informed of an outbreak of respiratory disease in China affecting the city of Wuhan in Hubei province. The cause of the outbreak has since been identified as due to a newly identified coronavirus, now called SARS-CoV-2. The infection is formally called coronavirus disease (COVID-19).
On 30 January 2020, WHO declared the COVID-19 outbreak was a public health emergency of international concern.
On 11 March 2020, WHO characterised the COVID-19 outbreak as a pandemic, the first pandemic caused by a coronavirus.