New crowns are generally not contagious when cured, but may still be contagious if there is a reversion to positive. If a person is inadvertently infected with the new crown virus and is discharged or released from isolation after treatment or intensive isolation, he or she is generally not contagious. At this time, the number and load of viruses in the body are at a low level and can be completely eliminated by the body’s own immunity, and no new infectious viruses will be produced, so it is not contagious. However, some infected persons may experience a relapse of the virus after treatment. At this time, the virus in the body is still contagious, so it can continue to spread through the respiratory tract, and it is necessary to undergo centralized quarantine or treatment again, and only after complete recovery can it lose its contagiousness completely.