In December 2019, an outbreak of pneumonia of unknown origin was observed in the city of Wuhan, Hubei Province, China. A novel coronavirus, the 2019 new coronavirus, then named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified as the etiologic agent responsible for the outbreak.
1,2 Coronavirus disease 2019 (COVID-19) then spread outside Hubei to many countries outside China. It was defined as a pandemic by the World Health Organization on March 11, 2020.
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