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arXiv · 2309.14801

Increasing situational awareness through nowcasting of the reproduction number

Andrea Bizzotto·Giorgio Guzzetta·Valentina Marziano·Martina del Manso·Alberto Mateo Urdiales·Daniele Petrone·Andrea Cannone·Chiara Sacco·Piero Poletti·Mattia Manica·Agnese Zardini·Filippo Trentini·Massimo Fabiani·Antonino Bella·Flavia Riccardo·Patrizio Pezzotti·Marco Ajelli·Stefano Merler
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Abstract

The time varying reproduction number R is a critical variable for situational awareness during infectious disease outbreaks, but delays between infection and reporting hinder its accurate estimation in real time. We propose a nowcasting method for improving the timeliness and accuracy of R estimates, based on comparisons of successive versions of surveillance databases. The method was validated against COVID-19 surveillance data collected in Italy over an 18-month period. Compared to traditional methods, the nowcasted reproduction number reduced the estimation delay from 13 to 8 days, while maintaining a better accuracy. Moreover, it allowed anticipating the detection of periods of epidemic growth by between 6 and 23 days. The method offers a simple and generally applicable tool to improve situational awareness during an epidemic outbreak, allowing for informed public health response planning.

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Andrea Bizzotto, Giorgio Guzzetta, Valentina Marziano, Martina del Manso, Alberto Mateo Urdiales, Daniele Petrone, Andrea Cannone, Chiara Sacco, Piero Poletti, Mattia Manica, Agnese Zardini, Filippo Trentini, Massimo Fabiani, Antonino Bella, Flavia Riccardo, Patrizio Pezzotti, Marco Ajelli, Stefano Merler. 2023-09-26. Increasing situational awareness through nowcasting of the reproduction number. https://arxiv.org/abs/2309.14801

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