Before revision: In this work we report that the public reacted on social media at an early stage of the SARS-CoV-2 pandemic, the virus responsible of COVID-19 , in a surprisingly accurate way. Early social media activity levels reflected the severity of the disease as registered almost a month later.
After revision: In this work we report that the public reacted on social media at an early stage of the SARS-CoV-2 pandemic, the virus responsible of COVID-19 related tweet at the beginning of the pandemic across Italian, Spanish and USA regions and mortality in the region a month later.