Emergencies

Zika situation report

1 September 2016

Zika virus, Microcephaly and Guillain-Barré syndrome

Key updates

  • Countries and territories reporting mosquito-borne Zika virus infections for the first time in the past week:
    • British Virgin Islands and Singapore
  • Countries and territories reporting microcephaly and other central nervous system (CNS) malformations potentially associated with Zika virus infection for the first time in the past week:
    • None
  • Countries and territories reporting Guillain-Barré syndrome (GBS) cases associated with Zika virus infection for the first time in the past week:
    • None
  • Operational updates from the WHO Regional Office for the Americas:
    • WHO provided technical advice on the detection of and response to congenital syndromes, and the care of pregnant women and newborn children in the Dominican Republic.
  • The 2016 Summer Paralympic Games will be held in Rio de Janeiro, Brazil, from 7 to 18 September. WHO continues to provide technical support to the Ministry of Health to ensure the 2016 Summer Paralympic Games are as safe as possible for all athletes, volunteers, visitors and residents.
  • Genetic sequencing of Zika virus isolates from four samples collected in Guinea-Bissau has preliminarily identified that these are related to the African lineage of the virus.

Summary

  • 72 countries and territories (Fig. 1, Table 1) have reported evidence of mosquito-borne Zika virus transmission since 2007 (69 with reports from 2015):
    • 55 with a first reported outbreak from 2015 onward (Fig. 2, Table 1).
    • 4 with having possible endemic transmission or evidence of local mosquito-borne Zika infections in 2016.
    • 13 with evidence of local mosquito-borne Zika infections in or before 2015, but without documentation of cases in 2016, or with the outbreak terminated.
  • Since February 2016, 11 countries have reported evidence of person-to-person transmission of Zika virus (Table 2).
  • 20 countries or territories have reported microcephaly and other CNS malformations potentially associated with Zika virus infection or suggestive of congenital infection (Table 3). 4 of the 20 countries reported microcephalic babies born from mothers in countries with no endemic Zika virus transmission but who reported recent travel history to Zika-affected countries.
  • Outcomes of pregnancies with laboratory evidence of possible Zika virus in the United States of America:
    • 16 total liveborn infants with birth defects
    • 5 total pregnancy losses with birth defects
  • Outcomes of pregnancies with laboratory evidence of possible Zika virus in territories of the United States of America:
    • 1 total liveborn infant with birth defects
    • 1 total pregnancy loss with birth defects
  • 18 countries and territories have reported an increased incidence of GBS and/or laboratory confirmation of a Zika virus infection among GBS cases (Table 4).
  • In Guinea-Bissau, the gene sequencing results of the four confirmed Zika cases sent in July have preliminarily confirmed that the cases are of the African lineage, i.e., not the predominant global outbreak Asian lineage. The investigation of five reported cases of microcephaly is ongoing.
  • The 2016 Summer Paralympic Games will be held in Rio de Janeiro, Brazil, from 7 to 18 September. WHO, particularly through the Regional Office for the Americas, continues to provide technical support to the Ministry of Health to ensure the 2016 Summer Paralympic Games are as safe as possible for all athletes, volunteers, visitors and residents.

This page links all WHO information to its response on the Public Health Emergency of International Concern.