Zika virus: a previously slow pandemic spreads rapidly through the Americas

Zika virus (Flaviviridae) is an emerging arbovirus. Spread by Aedes mosquitoes, it was first discovered in Uganda in 1947, and later in humans elsewhere in sub-Saharan Africa, arriving in south-east Asia at latest by mid-20th-century. In the 21st century, it spread across the Pacific Islands reaching South America around 2014. Since then it has spread rapidly northwards reaching Mexico in November 2015. Its clinical profile is that of a dengue-like febrile illness, but recently associations with Guillain-Barré syndrome and microcephaly have appeared. The final geographical range and ultimate clinical impact of Zika virus are still a matter for speculation