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Duration of infectiousness and correlation with RT-PCR cycle threshold values in cases of COVID-19, England, January to May 2020.

ABSTRACT: Severe acute respiratory syndrome coronavirus 2 viral load in the upper respiratory tract peaks around symptom onset and infectious virus persists for 10 days in mild-to-moderate coronavirus disease (n?=?324 samples analysed). RT-PCR cycle threshold (Ct) values correlate strongly with cultivable virus. Probability of culturing virus declines to 8% in samples with Ct?>?35 and to 6% 10 days after onset; it is similar in asymptomatic and symptomatic persons. Asymptomatic persons represent a source of transmissible virus.

SUBMITTER: Singanayagam A

PROVIDER: S-EPMC7427302 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Duration of infectiousness and correlation with RT-PCR cycle threshold values in cases of COVID-19, England, January to May 2020.

Singanayagam Anika A Patel Monika M Charlett Andre A Lopez Bernal Jamie J Saliba Vanessa V Ellis Joanna J Ladhani Shamez S Zambon Maria M Gopal Robin R

Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin 20200801 32

Severe acute respiratory syndrome coronavirus 2 viral load in the upper respiratory tract peaks around symptom onset and infectious virus persists for 10 days in mild-to-moderate coronavirus disease (n = 324 samples analysed). RT-PCR cycle threshold (Ct) values correlate strongly with cultivable virus. Probability of culturing virus declines to 8% in samples with Ct > 35 and to 6% 10 days after onset; it is similar in asymptomatic and symptomatic persons. Asymptomatic persons represent a source ...[more]

PMID: 32794447

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