2015–16 Zika virus epidemic
An epidemic of Zika fever, caused by Zika virus, began in Brazil and affected other countries in the Americas from April 2015 to November 2016. The World Health Organization (WHO) declared the end of the epidemic in November 2016, but noted that the virus still represents "a highly significant and long term problem".
Source: Wikipedia — 2015–16 Zika virus epidemic (CC BY-SA 4.0)