The onset of the new coronavirus is winter and spring, which may overlap with the onset of influenza and winter and spring diseases that are easily prevalent, so it needs to be differentiated to rule out pneumonia caused by the new coronavirus, which needs to be judged from an infectious disease perspective, without a history of epidemiology, no visit to an infected area, no history of close contact, etc. Screening is performed first to rule out. Based on laboratory tests, routine blood tests, if the routine blood test is elevated white blood cells, bacterial infection may be considered instead of viral infection, and CT manifestation is not like viral pneumonia, but bacterial pneumonia such as lobar pneumonia, then infection caused by neo-coronavirus is not considered. The most important thing is nucleic acid testing and pathogenic testing, to check positive nucleic acid, sometimes check once negative nucleic acid can not be completely excluded, probably the current exclusion criteria should be checked at least twice, and need to check every other day, and at the same time combined with other manifestations, including laboratory tests, epidemiology, basically can exclude the possibility of new coronavirus infection. Content source: Dr. You Lai