Epidemiological update: Outbreaks of Zika virus and complications potentially linked to the Zika virus infection, 17 November 2016

Since 2015, and as of 10 November 2016, there have been 71 countries and territories reporting mosquito-borne transmission of the virus. According to WHO and as of 9 November 2016, 26 countries or territories have reported microcephaly and other central nervous system (CNS) malformations in newborns potentially associated with Zika virus infection.

Weekly Summary

In the USA, 15 new locally-acquired cases have been reported in Florida since the last CDTR. Additionally, 19 cases have been reported, following a change in the CDC national Zika case definition on 9 November.

Montserrat has been designated as high risk for Zika transmission on the Public Health England website and has been added to the ECDC map.

On 8 November, Palau reported the first autochthonous Zika case.

ECDC Zika map: Montserrat and Palau have been displayed on the map as countries with sporadic transmission. In addition, Turks and Caicos Islands and British Virgin Islands have changed the status to widespread transmission.

Epidemiological Summary

1. Update on number of cases

USA: In the USA, 15 new locally-acquired cases have been reported in Florida since the last CDTR. Additionally, 19 cases have been reported, following a change in the CDC national Zika case definition on 9 November. To date, 222 locally-acquired and 915 imported cases of Zika have been reported in Florida.

EU/EEA imported cases Since July 2015 (week 26), 20 countries (Austria, Belgium, the Czech Republic, Denmark, Finland, France, Hungary, Ireland, Italy, Luxembourg, Malta, the Netherlands, Norway, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden and the United Kingdom) have reported 1 967 travel-associated Zika virus infections through The European Surveillance System (TESSy). Over the same time period, eight EU countries reported 95 Zika cases among pregnant women. EU’s Outermost Regions and Territories As of epidemiological week 42, the overall number of cases has been decreasing in all the French Outermost Territories with 40 suspected cases reported in Martinique, 30 in French Guiana, 50 in Guadeloupe, 30 in St Barthelemy, 40 in St Martin. Since February 2016, 12 countries have reported evidence of person-to-person transmission of Zika virus, probably via a sexual route. 2. Update on microcephaly and/or central nervous system (CNS) malformations potentially associated with Zika virus infection As of 10 November 2016, microcephaly and other central nervous system (CNS) malformations associated with Zika virus infection or suggestive of congenital infection have been reported by 26 countries or territories. Brazil reports the highest number of cases. Nineteen 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. 

ECDC Assessment

The spread of the Zika virus in the Americas and Asia is likely to continue as the vectors (Aedes aegypti and Aedes albopictus mosquitoes) are widely distributed there. The likelihood of travel-related cases in the EU is increasing. A detailed risk assessment was published on 28 October 2016. As neither treatment nor vaccines are available, prevention is based on personal protection measures. Pregnant women should consider postponing non-essential travel to Zika-affected areas.

Countries and territories with reported confirmed autochthonous cases of Zika virus infection in the past three months, as of 11 November 2016

The classification of countries above is based on: 1) number of reported autochthonous confirmed cases; 2) number of countries who report a zika virus transmission or a country’s transmission status changes; 3) duration of the circulation.

Countries or territories with reported confirmed autochthonous cases of Zika virus infection in the past three months, as of 11 November 2016

All latest ECDC maps with information on countries or territories with reported confirmed autochthonous cases of Zika virus infection.