Zika situation report
17 March 2016
Zika virus, Microcephaly and Guillain-Barré syndrome
- From 1 January 2007 to 16 March 2016, Zika virus transmission was documented in a total of 59 countries and territories. Cuba and Dominica are the latest to report autochthonous (local) transmission of Zika virus on 14 and 15 March, respectively. Five of these countries and territories reported a Zika virus outbreak that is now over. Three countries (France, Italy and United States of America) have reported locally acquired infection in the absence of any known mosquito vectors, probably through sexual transmission.
- The geographical distribution of Zika virus has steadily widened since the virus was first detected in the Americas in 2014. Autochthonous Zika virus transmission has been reported in 33 countries and territories of this region.
- So far an increase in microcephaly and other fetal malformations has been reported in Brazil and French Polynesia, although two additional cases linked to a stay in Brazil were detected in the United States of America and Slovenia.
- In the context of Zika virus circulation 12 countries or territories have reported an increased incidence of Guillain-Barré syndrome (GBS) and/or laboratory confirmation of a Zika virus infection among GBS cases.
- The mounting evidence from observational, cohort and case-control studies indicates that Zika virus is highly likely to be a cause of microcephaly, GBS and other neurologic disorders. Among the tasks ahead are to further quantify the risk of neurologic disorders following Zika virus infection, and to investigate the biological mechanisms that lead to neurologic disorders.
- The global prevention and control strategy launched by WHO as a Strategic Response Framework encompasses surveillance, response activities and research, and this situation report is organized under those headings.