Il sistema di sorveglianza basato su eventi in Italia dal 2009 al 2021. Verso una intelligence di sanità pubblica

The Italian event-based surveillance system from 2009 to 2021: towards public health intelligence Introduction Event-based surveillance (EBS) complements traditional surveillance to identify, track and critically appraise the potential public health (PH) impact of infectious diseases and other health threats. The Ministry of Health, the Istituto Superiore di Sanità, regional health authorities with the support of international partnerships shaped EBS in Italy into a flexible, decentralized, and sustainable system that operates through the existing public health workforce with no additional costs. We report the early activation of EBS in Italy, from mass gatherings to its systematic contribution to risk monitoring during the COVID-19 pandemic. Materials and methods Italian EBS analysts aim to detect cases/clusters of infectious diseases of PH impact in Italy mainly monitoring MedISys and Google Alerts. A risk assessment matrix was designed to favour coherence in the classification of events. In 2019, the analysts assessed the sustainability of the operations model though an online survey. Results Training and an adapted operation model established an Italian Epidemic Intelligence Network comprising over 20 analysts in 2019 and led to the formal recognition of EBS in 2021. The Italian EBS captured and reported over 500 events since 2018 with a positive predictive value of validated events consistently above 85%. Sustainability of the operations model was confirmed by the analysts, defining the approach still in use today. Discussion and conclusions The COVID-19 pandemic has broadened the scope of PH Intelligence as a core function of PH for preparedness against epidemic/pandemic threats. The Italian EBS must step up to its formal recognition in the context of this broader global mandate, thus completing its transition from proof of concept to PH asset. Key words: event-based surveillance; epidemic Intelligence; early detection