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arXiv · 2006.08471

Probability of symptoms and critical disease after SARS-CoV-2 infection

Piero Poletti·Marcello Tirani·Danilo Cereda·Filippo Trentini·Giorgio Guzzetta·Giuliana Sabatino·Valentina Marziano·Ambra Castrofino·Francesca Grosso·Gabriele Del Castillo·Raffaella Piccarreta·ATS Lombardy COVID-19 Task Force·Aida Andreassi·Alessia Melegaro·Maria Gramegna·Marco Ajelli·Stefano Merler
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Abstract

We quantified the probability of developing symptoms (respiratory or fever \geq 37.5 {\deg}C) and critical disease (requiring intensive care or resulting in death) of SARS-CoV-2 positive subjects. 5,484 contacts of SARS-CoV-2 index cases detected in Lombardy, Italy were analyzed, and positive subjects were ascertained via nasal swabs and serological assays. 73.9% of all infected individuals aged less than 60 years did not develop symptoms (95% confidence interval: 71.8-75.9%). The risk of symptoms increased with age. 6.6% of infected subjects older than 60 years had critical disease, with males at significantly higher risk.

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Piero Poletti, Marcello Tirani, Danilo Cereda, Filippo Trentini, Giorgio Guzzetta, Giuliana Sabatino, Valentina Marziano, Ambra Castrofino, Francesca Grosso, Gabriele Del Castillo, Raffaella Piccarreta, ATS Lombardy COVID-19 Task Force, Aida Andreassi, Alessia Melegaro, Maria Gramegna, Marco Ajelli, Stefano Merler. 2020-06-15. Probability of symptoms and critical disease after SARS-CoV-2 infection. https://doi.org/10.1001/jamanetworkopen.2021.1085

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