Valutare l'impatto di eventi esogeni sulla mobilità umana mediante tracce digitali

Despite being some of the oldest policies intended to contain the spread of highly infectious diseases, the effectiveness of travel restrictions and advisory has recently been questioned in several empirical studies. However, while much attention has been given to the analysis of long-range travel control measures, the impact of travel guides on short-range human mobility is still largely unexplored. Additionally, due to the unavailability of official data the role of compliance to advisories and the behavioural changes associated with the disease spreading are poorly studied, especially at a local level. Here we present the assessment of the effectiveness of the Center For Disease Control and Prevention travel advisory issued in response to the 2016 Zika Virus spread in the continental US. To do so, we analyze a rich dataset of over 4 billion data points relative to the location of almost 15 million anonymized users between December 2015 and July 2017. To evaluate the policy effectiveness, we have compared the target of the treatment to a synthetic counterfactual built using two different data-driven methodologies. Our analysis reveals a slight impact of the travel advisory, limited to the first month after the treatment and restricted to a specific group of users.