People with new crown re-positive can excrete the pathogen, so it is contagious, and should pay attention to isolation and protection. New crown re-positive refers to the body was once infected with the new crown virus, the body after the virus clearance (usually based on non-simultaneous multiple nucleic acid test are negative and the disappearance of clinical symptoms), and then again appeared positive nucleic acid situation. Once it is confirmed that the nucleic acid has turned positive, the person can be recognized as a new coronavirus re-positive person. This group of people can excrete the new coronavirus pathogen into the external environment, and their close contacts are more likely to be infected if they are not immunized. Therefore, if there is a resurgence of the new coronavirus, attention must be paid to early detection, early isolation and early treatment. Timely report to the relevant departments to avoid the spread of the epidemic and transmission.