Even before the appearance of COVID-19 cases in Italy, a group led by Prof. Zehender at the University of Milan performed a temporal reconstruction of the SARS-CoV-2 phylogeny.7 The results suggest that the epidemic originated between October and November 2019, a few weeks before the identification of the first cases. We now know that this is spot on, since the first confirmed case reported has been fixed at November 17th.8 Analysis of the reproduction number R of the virus (i.e., the number of secondary cases induced by a single infected individual) increased in December 2019, leading to the current pandemic (Figure 2). R usually decreases over the course of an epidemic, due to the reduced number of susceptible individuals, but in this case the increase might be due to the acquisition of a more efficient human-to-human transmission trait (i.e., via the now infamous droplets).