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SARS-CoV-2: The viral shedding vs infectivity dilemma

      Highlights

      • Viral shedding has been demonstrated up to 63 days after symptom onset.
      • The distinction between viral shedding and infectivity is important for the development of quarantine guidelines and policy.
      • There is an earlier peak in viral load in SARS-CoV-2 than seen in SARS.
      • Quantitative viral loads are higher in the nose than the throat.
      • It is likely that asymptomatic and presymptomatic transmission is occurring.

      Abstract

      Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected over four million people worldwide. There are multiple reports of prolonged viral shedding in people infected with SARS-CoV-2 but the presence of viral RNA on a test does not necessarily correlate with infectivity. The duration of quarantine required after clinical recovery to definitively prevent transmission is therefore uncertain. In addition, asymptomatic and presymptomatic transmission may occur, and infectivity may be highest early after onset of symptoms, meaning that contact tracing, isolation of exposed individuals and social distancing are essential public health measures to prevent further spread. This review aimed to summarise the evidence around viral shedding vs infectivity of SARS-CoV-2.

      Keywords

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