What is it about?

The reproduction number Rt indicates the average number of cases generated by an infected person at time t and is a key indicator of the spread of an epidemic. EpiInvert estimates Rt by inverting the renewal equation using a variational approach. EpiInvert can be run in real-time on every country in the world, and every US state through a web interface at www.ipol.im/epiinvert.

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Why is it important?

EpiInvert estimates Rt several days in advance with respect to EpiEstim (the most widely accepted method for estimating Rt). Using Rt and the renewal equation, EpiInvert also computes a restored version of the daily incidence curve more current to study the epidemic trend than the usual average of the last 7 days. These facts are extremely relevant, given that the control of social distancing policies requires a timely estimate of Rt and the epidemic trend.


I believe that this work introduces a new approach to estimate Rt based on the inversion of the renewal equation that is completely different from the usual statistical formulation and that hopefully can help in making decisions related to the control of the COVID-19 epidemic.

Luis Alvarez
Universidad de Las Palmas de Gran Canaria

Read the Original

This page is a summary of: Computing the daily reproduction number of COVID-19 by inverting the renewal equation using a variational technique, Proceedings of the National Academy of Sciences, December 2021, Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.2105112118.
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