Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Aug;25(32):2001483.
doi: 10.2807/1560-7917.ES.2020.25.32.2001483.

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

Anika Singanayagam  1   2 , Monika Patel  1   2 , Andre Charlett  3 , Jamie Lopez Bernal  4 , Vanessa Saliba  4 , Joanna Ellis  1 , Shamez Ladhani  4 , Maria Zambon  1 , Robin Gopal  1
Affiliations

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

Anika Singanayagam et al. Euro Surveill. 2020 Aug.

Erratum in

  • Correction for Euro Surveill. 2020;25(32).
    Eurosurveillance editorial team. Eurosurveillance editorial team. Euro Surveill. 2021 Feb;26(7):210218c. doi: 10.2807/1560-7917.ES.2021.26.7.210218c. Euro Surveill. 2021. PMID: 33602383 Free PMC article. No abstract available.

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.

Keywords: COVID-19; SARS-CoV-2; coronavirus; infectiousness; public health policy; respiratory virus.

PubMed Disclaimer

Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure 1
Figure 1
Detection of SARS-CoV-2 by RT-PCR targeting the RdRp gene, England, January–April 2020 (n = 754)
Figure 2
Figure 2
Relationship between RT-PCR Ct value and culture positivity in mixed effects logistic regression analysis, SARS-CoV-2, England, January–May 2020 (n = 324)
Figure 3
Figure 3
Relationship between culture positivity and time between symptom onset and sample collection, SARS-CoV-2, England, January–May 2020 (n = 246)
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Corman VM, Landt O, Kaiser M, Molenkamp R, Meijer A, Chu DK, et al. Detection of 2019 novel coronavirus (2019-nCoV) by real-time RT-PCR. Euro Surveill. 2020;25(3):2000045. 10.2807/1560-7917.ES.2020.25.3.2000045 - DOI - PMC - PubMed
    1. Boddington NL, Charlett A, Elgohari S, Walker JL, Mcdonald H, Byers C, et al. COVID-19 in Great Britain: epidemiological and clinical characteristics of the first few hundred (FF100) cases: a descriptive case series and case control analysis. medRxiv. 2020.05.18.20086157. Available from: http://medrxiv.org/content/early/2020/05/22/2020.05.18.20086157
    1. World Health Organization (WHO). Clinical management of COVID-19 (interim guidance). Geneva: WHO; 27 May 2020. Available from: https://www.who.int/publications-detail/clinical-management-of-covid-19
    1. Department of Health and Social Care. Statement from the UK Chief Medical Officers on extension of self-isolation period: 30 July 2020. London: Department of Health and Social Care; 30 July 2020. Available from: https://www.gov.uk/government/news/statement-from-the-uk-chief-medical-o...
    1. Wölfel R, Corman VM, Guggemos W, Seilmaier M, Zange S, Müller MA, et al. Virological assessment of hospitalized patients with COVID-2019. Nature. 2020;581(7809):465-9. 10.1038/s41586-020-2196-x - DOI - PubMed

MeSH terms

LinkOut - more resources