Frontiers in Public Health (Aug 2024)

Increasing situational awareness through nowcasting of the reproduction number

  • Andrea Bizzotto,
  • 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,
  • Filippo Trentini,
  • Massimo Fabiani,
  • Antonino Bella,
  • Flavia Riccardo,
  • Patrizio Pezzotti,
  • Marco Ajelli,
  • Stefano Merler

DOI
https://doi.org/10.3389/fpubh.2024.1430920
Journal volume & issue
Vol. 12

Abstract

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BackgroundThe time-varying reproduction number R is a critical variable for situational awareness during infectious disease outbreaks; however, delays between infection and reporting of cases hinder its accurate estimation in real-time. A number of nowcasting methods, leveraging available information on data consolidation delays, have been proposed to mitigate this problem.MethodsIn this work, we retrospectively validate the use of a nowcasting algorithm during 18 months of the COVID-19 pandemic in Italy by quantitatively assessing its performance against standard methods for the estimation of R.ResultsNowcasting significantly reduced the median lag in the estimation of R from 13 to 8 days, while concurrently enhancing accuracy. Furthermore, it allowed the detection of periods of epidemic growth with a lead of between 6 and 23 days.ConclusionsNowcasting augments epidemic awareness, empowering better informed public health responses.

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