The presence of viral RNA in respiratory samples is critical information in the diagnosis of an acute SARS-COV-2 infection. The real-time reverse transcription-polymerase chain reaction (RT-PCR) detects these pieces of RNA. But RT-PCR is a poor test of cure. The presence of RNA does not imply the presence of infectious or replication-competent virus.
Retesting after a positive PCR outcome for SARS-CoV-2