The median time from discharge to SARS - CoV - 2 nucleic acid re - positive was 4 days ( IQR , 3 - 8 . 5 ) . The median time from symptoms onset to final respiratory SARS - CoV - 2 detection of negative result was significantly longer in re - positive group ( 34 days [ IQR , 29 . 5 - 42 . 5 ] ) than in