Several pneumonia cases were discovered in late 2019, with clinical presentations resembling viral pneumonia. Pathogenic gene sequencing confirmed that the pathogen was a novel coronavirus, which was named 2019 novel coronavirus (SARS-CoV-2). Similar to previous outbreaks of coronavirus infection in humans, SARS-CoV-2 infection caused the novel corona virus disease (COVID-19) and the outbreak developed into an epidemic that quickly spread all over the world, resulting in public health emergencies around the world.