The unmitigated profile of COVID-19 infectiousness
- Weizmann Institute of Science, Israel
- Princeton University, United States
- McMaster University, Canada
Abstract
Quantifying the temporal dynamics of infectiousness of individuals infected with SARS-CoV-2 is crucial for understanding the spread of COVID-19 and for evaluating the effectiveness of mitigation strategies. Many studies have estimated the infectiousness profile using observed serial intervals. However, statistical and epidemiological biases could lead to underestimation of the duration of infectiousness. We correct for these biases by curating data from the initial outbreak of the pandemic in China (when mitigation was minimal), and find that the infectiousness profile of the original strain is longer than previously thought. Sensitivity analysis shows our results are robust to model structure, assumed growth rate and potential observational biases. Although unmitigated transmission data is lacking for variants of concern (VOC), previous analyses suggest that the alpha and delta variants have faster within-host kinetics, which we extrapolate to crude estimates of variant-specific unmitigated generation intervals. Knowing the unmitigated infectiousness profile of infected individuals can inform estimates of the effectiveness of isolation and quarantine measures. The framework presented here can help design better quarantine policies in early stages of future epidemics.
Data availability
All study data are included in the article, SI appendix, and Dataset S1.All code is available in Jupyter notebooks found inhttps://gitlab.com/milo-lab-public/the-unmitigated-profile-of-covid-19-infectiousness
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Supplementary Table 8. Dates of symptom onset of infector-infectee pairsSupplementary Table 8. Dates of symptom onset of infector-infectee pairs.
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Zhao et al. supplementary material 1Zhao et al. supplementary material 1.
Article and author information
Author details
Funding
Weizmann Institute of Science (The Weizmann CoronaVirus Fund)
- Ron Milo
Weizmann Institute of Science (Weizmann Data Science Research Center,and by a research grant from the Estate of Tully and Michele)
- Ron Sender
Canadian Institute for Health Research
- Jonathan Dushoff
Ben B. and Joyce E. Eisenberg Foundation
- Ron Milo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Sender et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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The unmitigated profile of COVID-19 infectiousness
eLife 11:e79134.
https://doi.org/10.7554/eLife.79134
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