TY - JOUR T1 - Magnitude and time-course of excess mortality during COVID-19 outbreak: population-based empirical evidence from highly impacted provinces in northern Italy JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00458-2020 VL - 6 IS - 3 SP - 00458-2020 AU - Sara Conti AU - Pietro Ferrara AU - Giampiero Mazzaglia AU - Marco I. D'Orso AU - Roberta Ciampichini AU - Carla Fornari AU - Fabiana Madotto AU - Michele Magoni AU - Giuseppe Sampietro AU - Andrea Silenzi AU - Claudio V. Sileo AU - Alberto Zucchi AU - Giancarlo Cesana AU - Lamberto Manzoli AU - Lorenzo G. Mantovani Y1 - 2020/07/01 UR - http://openres.ersjournals.com/content/6/3/00458-2020.abstract N2 - Background The real impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on overall mortality remains uncertain as surveillance reports have attributed a limited number of deaths to novel coronavirus disease 2019 (COVID-19) during the outbreak. The aim of this study was to assess the excess mortality during the COVID-19 outbreak in highly impacted areas of northern Italy.Methods We analysed data on deaths that occurred in the first 4 months of 2020 provided by the health protection agencies (HPAs) of Bergamo and Brescia (Lombardy), building a time-series of daily number of deaths and predicting the daily standardised mortality ratio (SMR) and cumulative number of excess deaths through a Poisson generalised additive model of the observed counts in 2020, using 2019 data as a reference.Results We estimated that there were 5740 (95% credible set (CS) 5552–5936) excess deaths in the HPA of Bergamo and 3703 (95% CS 3535–3877) in Brescia, corresponding to a 2.55-fold (95% CS 2.50–2.61) and 1.93 (95% CS 1.89–1.98) increase in the number of deaths. The excess death wave started a few days later in Brescia, but the daily estimated SMR peaked at the end of March in both HPAs, roughly 2 weeks after the introduction of lockdown measures, with significantly higher estimates in Bergamo (9.4, 95% CI 9.1–9.7).Conclusion Excess mortality was significantly higher than that officially attributed to COVID-19, disclosing its hidden burden likely due to indirect effects on the health system. Time-series analyses highlighted the impact of lockdown restrictions, with a lower excess mortality in the HPA where there was a smaller delay between the epidemic outbreak and their enforcement.This study identifies another important element to research on #SARSCoV2 and provides actionable strategies to quantify the excess mortality due to #COVID19 spread, which has public health and research implications to minimise the disease impact https://bit.ly/3jbKXAW ER -