Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Aug;25(31):2001383.
doi: 10.2807/1560-7917.ES.2020.25.31.2001383.

Age-specific SARS-CoV-2 infection fatality ratio and associated risk factors, Italy, February to April 2020

Piero Poletti  1 , Marcello Tirani  2   3 , Danilo Cereda  2 , Filippo Trentini  1 , Giorgio Guzzetta  1 , Valentina Marziano  1 , Sabrina Buoro  2   4 , Simona Riboli  5 , Lucia Crottogini  2 , Raffaella Piccarreta  6   7 , Alessandra Piatti  2 , Giacomo Grasselli  8   9 , Alessia Melegaro  10   6 , Maria Gramegna  2 , Marco Ajelli  11 , Stefano Merler  1
Affiliations

Age-specific SARS-CoV-2 infection fatality ratio and associated risk factors, Italy, February to April 2020

Piero Poletti et al. Euro Surveill. 2020 Aug.

Abstract

We analysed 5,484 close contacts of coronavirus disease (COVID-19) cases in Italy, all tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Infection fatality ratio was 0.43% (95% confidence interval (CI): 0.21-0.79) for individuals younger than 70 years and 10.5% (95% CI: 8.0-13.6) for older individuals. Risk of death after infection was 62% lower (95% CI: 31-80) in clusters identified after 16 March 2020 and 1.8-fold higher for males (95% CI: 1.03-3.16).

Keywords: COVID-19; SARS-CoV-2; comorbidities; infection fatality ratio; mortality.

PubMed Disclaimer

Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure
Figure
Age-specific estimates (mean) of infection fatality ratio, SARS-CoV-2-positive contacts, Lombardy, Italy, February–April 2020 (n = 2,824)
See this image and copyright information in PMC

References

    1. Okell LC, Verity R, Watson OJ, Mishra S, Walker P, Whittaker C, et al. Have deaths from COVID-19 in Europe plateaued due to herd immunity? Lancet. 2020;395(10241):e110-1. 10.1016/S0140-6736(20)31357-X - DOI - PMC - PubMed
    1. Verity R, Okell LC, Dorigatti I, Winskill P, Whittaker C, Imai N, et al. Estimates of the severity of coronavirus disease 2019: a model-based analysis. Lancet Infect Dis. 2020;20(6):669-77. 10.1016/S1473-3099(20)30243-7 - DOI - PMC - PubMed
    1. Grasselli G, Zangrillo A, Zanella A, Antonelli M, Cabrini L, Castelli A, et al. Baseline characteristics and outcomes of 1591 patients infected with SARS-CoV-2 admitted to ICUs of the Lombardy region, Italy. JAMA. 2020;323(16):1574-81. 10.1001/jama.2020.5394 - DOI - PMC - PubMed
    1. Meyerowitz-Katz G and Merone L (2020) A systematic review and meta-analysis of published research data on COVID-19 infection-fatality rates. medRxiv. 2020. Available from: https://doi.org/10.1101/2020.05.03.20089854 - PMC - PubMed
    1. Cereda D, Tirani M, Rovida F, Demicheli V, Ajelli M, Poletti P, et al. The early phase of the COVID-19 outbreak in Lombardy, Italy. arXiv. 2020. Available from: https://arxiv.org/abs/2003.09320

MeSH terms