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Real-Time Estimation of R_t for Supporting Public-Health Policies Against COVID-19

Contreras, Sebastián and Villavicencio, H. Andrés and Medina-Ortiz, David and Saavedra, Claudia P. and Olivera-Nappa, Álvaro (2020) Real-Time Estimation of R_t for Supporting Public-Health Policies Against COVID-19. Frontiers in Public Health, 8 . Art. No. 556689. ISSN 2296-2565. PMCID PMC7783316. doi:10.3389/fpubh.2020.556689.

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In the absence of a consensus protocol to slow down the spread of SARS-CoV-2, policymakers need real-time indicators to support decisions in public health matters. The Effective Reproduction Number (R_t) represents the number of secondary infections generated per each case and can be dramatically modified by applying effective interventions. However, current methodologies to calculate R_t from data remain somewhat cumbersome, thus raising a barrier between its timely calculation and application by policymakers. In this work, we provide a simple mathematical formulation for obtaining the effective reproduction number in real-time using only and directly daily official case reports, obtained by modifying the equations describing the viral spread. We numerically explore the accuracy and limitations of the proposed methodology, which was demonstrated to provide accurate, timely, and intuitive results. We illustrate the use of our methodology to study the evolution of the pandemic in different iconic countries, and to assess the efficacy and promptness of different public health interventions.

Item Type:Article
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URLURL TypeDescription CentralArticle ItemData ItemData Paper
Contreras, Sebastián0000-0001-8909-774X
Medina-Ortiz, David0000-0002-8369-5746
Olivera-Nappa, Álvaro0000-0001-6053-7019
Alternate Title:Real-time estimation of R0 for supporting public-health policies against COVID-19, Real-time estimation of R₀ for supporting public-health policies against COVID-19
Additional Information:© 2020 Contreras, Villavicencio, Medina-Ortiz, Saavedra and Olivera-Nappa. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. Received: 13 May 2020; Accepted: 30 November 2020; Published: 22 December 2020. This manuscript has been released as a pre-print at (26). This research has been financed mainly by the Centre for Biotechnology and Bioengineering—CeBiB (PIA project FB0001, Conicyt, Chile). DM-O gratefully acknowledges Conicyt, Chile, for Ph.D. fellowship 21181435. The authors thank Prof. Francisco Melo for the helpful discussions on previous versions of our manuscript. Data Availability Statement: Publicly available datasets were analyzed in this study. This data can be found at:; Author Contributions: SC, DM-O, and HV: conceptualization, methodology, and investigation. ÁO-N, SC, and CS: validation. SC, DM-O, HV, and ÁO-N: writing, review, and editing. ÁO-N and CS: supervision and project administration. ÁO-N: funding resources. All authors contributed to the article and approved the submitted version. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Funding AgencyGrant Number
Centre for Biotechnology and BioengineeringUNSPECIFIED
Comisión Nacional de Investigación Científica y Tecnológica (CONICYT)FB0001
Comisión Nacional de Investigación Científica y Tecnológica (CONICYT)21181435
Subject Keywords:COVID-19, public-health policies, epidemiologic modeling, SARS-CoV-2, effective reproduction number R_t
PubMed Central ID:PMC7783316
Record Number:CaltechAUTHORS:20201120-072926742
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Official Citation:Contreras S, Villavicencio HA, Medina-Ortiz D, Saavedra CP and Olivera-Nappa Á (2020). Real-Time Estimation of Rt for Supporting Public-Health Policies Against COVID-19. Front. Public Health 8:556689. doi: 10.3389/fpubh.2020.556689
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:106750
Deposited By: Tony Diaz
Deposited On:20 Nov 2020 16:47
Last Modified:01 Jun 2023 23:54

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