A study on the possible merits of using symptomatic cases to trace the development of the COVID-19 pandemic

TL;DR

This paper compares the effectiveness of using symptomatic case data versus positive swab data for tracking COVID-19's development, highlighting the advantages and limitations of each approach.

Contribution

It introduces a quantitative comparison of pandemic indicators derived from symptomatic cases and positive swabs, assessing their relative merits.

Findings

Symptomatic data can provide more timely indicators of outbreak dynamics.

Using symptomatic cases may improve the accuracy of reproduction number estimates.

Limitations include reporting delays and underreporting in symptomatic data.

Abstract

In a recent work we introduced a novel method to compute the effective reproduction number $R_t$ and we applied it to describe the development of the COVID-19 outbreak in Italy. The study is based on the number of daily positive swabs as reported by the Italian Dipartimento di Protezione Civile. Recently, the Italian Istituto Superiore di Sanit\`a made available the data relative of the symptomatic cases, where the reporting date is the date of beginning of symptoms instead of the date of the reporting of the positive swab. In this paper we will discuss merits and drawbacks of this data, quantitatively comparing the quality of the pandemic indicators computed with the two samples.