New coronavirus infections may re-positive after cure and require nucleic acid testing and health surveillance as required. In the case of inadvertent infection with Neo-Crown virus, the possibility of re-positive infection still exists even after cure. Because the criterion for discharge from hospital is two consecutive negative nucleic acid tests (24 hours apart), some patients with neocoronavirus may not be able to detect the virus even after amplification due to the small amount of neocoronavirus remaining in their bodies, and may also have negative nucleic acid test results. Therefore, even if the patient is cured and discharged from the hospital, there may still be a small amount of neocoronavirus in the body. This may lead to relapse, especially if the infected person has low immunity and is unable to fight the virus through immunity. Therefore, nucleic acid testing and health monitoring are required, and immediate medical attention must be sought in the event of a positive test or symptoms such as fever.