title: Zika: the origin and spread of a mosquito-borne virus.
abstract: OBJECTIVE
  To describe the temporal and geographical distribution of Zika virus infection and associated neurological disorders, from 1947 to 1 February 2016, when Zika became a Public Health Emergency of International Concern (PHEIC).
  
  
  METHODS
  We did a literature search using the terms "Zika" and "ZIKV" in PubMed, cross-checked the findings for completeness against other published reviews and added formal notifications to WHO submitted under the International Health Regulations.
  
  
  RESULTS
  From the discovery of Zika virus in Uganda in 1947 to the declaration of a PHEIC by the World Health Organization (WHO) on 1 February 2016, a total of 74 countries and territories had reported human Zika virus infections. The timeline in this paper charts the discovery of the virus (1947), its isolation from mosquitos (1948), the first human infection (1952), the initial spread of infection from Asia to a Pacific island (2007), the first known instance of sexual transmission (2008), reports of Guillain-Barré syndrome (2014) and microcephaly (2015) linked to Zika infections and the first appearance of Zika in the Americas (from 2015).
  
  
  CONCLUSIONS
  Zika virus infection in humans appears to have changed in character as its geographical range has expanded from equatorial Africa and Asia. The change is from an endemic, mosquito-borne infection causing mild illness to one that can cause large outbreaks linked with neurological sequelae and congenital abnormalities.
authors.affiliation: World Health Organization, avenue Appia 20, 1211 Geneva 27, Switzerland .
authors.forename: Mary Kay
authors.initials: MK
authors.lastname: Kindhauser
authors.affiliation: World Health Organization, avenue Appia 20, 1211 Geneva 27, Switzerland .
authors.forename: Tomas
authors.initials: T
authors.lastname: Allen
authors.affiliation: World Health Organization, avenue Appia 20, 1211 Geneva 27, Switzerland .
authors.forename: Veronika
authors.initials: V
authors.lastname: Frank
authors.affiliation: World Health Organization, avenue Appia 20, 1211 Geneva 27, Switzerland .
authors.forename: Ravi Shankar
authors.initials: RS
authors.lastname: Santhana
authors.affiliation: World Health Organization, avenue Appia 20, 1211 Geneva 27, Switzerland .
authors.forename: Christopher
authors.initials: C
authors.lastname: Dye
mesh_terms: D000330:Aedes / Q000821:virology; D000349:Africa / Q000453:epidemiology; D000818:Animals; D001208:Asia / Q000453:epidemiology; D004196:Disease Outbreaks; D005843:Geography; D014943:Global Health; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D008253:Macaca mulatta / Q000821:virology; D008831:Microcephaly / Q000821:virology; D000071244:Zika Virus / Q000472:pathogenicity*; D000071243:Zika Virus Infection / Q000453:epidemiology* / Q000266:history / Q000503:physiopathology / Q000635:transmission*