SUMMARY
From 1 January 2007 to 20 April 2016, Zika virus transmission was documented in a total of 66 countries and territories.
Mosquito-borne transmission:
42 countries are experiencing a first outbreak of Zika virus since 2015, with no previous evidence of circulation, and with ongoing transmission by mosquitos.
17 countries have reported evidence of Zika virus transmission prior to 2015, with or without ongoing transmission or have reported an outbreak since 2015 that is now over.
Person-to-person transmission:
- Eight countries have now reported evidence of person-to-person transmission of Zika virus, other than mosquito-borne transmission (Argentina, Chile, France, Italy, New Zealand, Peru, Portugal and the United States of America).
In the week to 20 April, no additional countries have reported mosquito-borne Zika virus transmission. Peru and Portugal are the latest countries to report person-to-person transmission.
Microcephaly and other fetal malformations potentially associated with Zika virus infection or suggestive of congenital infection have been reported in six countries (Brazil, Cabo Verde, Colombia, French Polynesia, Martinique and Panama). Two cases, each linked to a stay in Brazil, were detected in Slovenia and the United States of America. A further case, linked to a brief stay in Mexico, Guatemala and Belize, was detected in a pregnant woman in the United States of America.
In the context of Zika virus circulation, 13 countries and territories worldwide have reported an increased incidence of Guillain-Barré syndrome (GBS) and/or laboratory confirmation of a Zika virus infection among GBS cases.
Based on a growing body of research, there is scientific consensus that Zika virus is a cause of microcephaly and GBS.
The global prevention and control strategy launched by the World Health Organization (WHO) as a Strategic Response Framework encompasses surveillance, response activities and research.
This situation report is organized under those headings.