Epidemiological update: Outbreaks of Zika virus and complications potentially linked to the Zika virus infection, 31 March 2016

​New developments since the last epidemiological update published on 18 March 2016

Since last week, Kosrae in the Federated States of Micronesia and Papua New Guinea have reported autochthonous transmission of Zika virus.

 

Chile: On 26 March, the Ministry of Health reported the first case of Zika virus infection through sexual transmission.

As of 31 March 2016, seven countries have reported non-vector-borne transmission of Zika virus, probably through sexual transmission: Argentina, Chile, France, Italy, New Zealand, Portugal (the Autonomous Region of Madeira) and the United States of America.

Publication

On 30 March, an article published in the New England Journal of Medicine describes an investigation into brain abnormalities detected in the foetus of a 33-year-old Finnish woman who was infected with Zika virus while on a trip to Mexico, Guatemala and Belize in November 2015, while she was 11 weeks pregnant. 

Detailed epidemiological situation

As of 31 March 2016, autochthonous cases of Zika virus infection have been reported from 45 countries and territories worldwide in the past two months (see Table 1 and Figure 1). Forty-seven countries and territories have reported autochthonous cases of Zika virus infection in the past nine months (see Table 1 and Figure 2).

 

Several countries in the Americas, Caribbean and the Pacific continue to report an increase in autochthonous cases of Zika virus infection.

Table 1. Countries and territories with reported confirmed autochthonous cases of Zika virus infection in the past two months, as of 31 March 2016

The classification of countries above is based on: 1) number of reported autochthonous confirmed cases; 2) number of affected areas in the country; 3) duration of the circulation.

EU/EEA and EU Outermost Regions and Territories

As of 31 March, no autochthonous Zika virus transmission has been reported in the continental EU. ECDC is collecting data regarding imported cases through the media and official government communication lines. As of 31 March 2016, ECDC has recorded 323 cases imported into 17 EU/EEA countries. In addition, one confirmed case has been published following diagnosis in a Slovenian hospital. Twenty cases are among pregnant women.

 

Several of the EU’s Outermost Regions and Territories continue to report autochthonous transmission.

 

Martinique: As of 31 March 2016, 15 440 suspected cases have been reported, an increase of 1 020 during the past week.

French Guiana: As of 31 March 2016, 3 190 suspected and 299 laboratory-confirmed cases have been reported, an increase of 410 suspected and 15 laboratory-confirmed cases during the past week.

 

Guadeloupe: As of 31 March 2016, 900 suspected and 139 laboratory-confirmed cases have been reported, an increase of 106 suspected and 5 laboratory-confirmed cases during the past week.

 

Saint Martin: As of 31 March, 157 suspected and 36 laboratory-confirmed cases have been reported, this is an increase of 3 suspected and six laboratory-confirmed cases during the past week.

Figure 1. Countries or territories with reported confirmed autochthonous cases of Zika virus infection in the past two months, as of 31 March 2016

Figure 2. Countries and territories with reported confirmed autochthonous cases of Zika virus infection in the past nine months, as of 31 March 2016

Update on the observed increase of congenital Zika syndrome and other neurological complications

In the context of Zika virus circulation, 13 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, according to WHO.

So far only French Polynesia and Brazil have reported an increase in Zika congenital syndrome.

 

Brazil: According to the Ministry of Health, since October 2015 and as of 29 March 2016, 6 776 suspected cases of microcephaly were reported from 1 285 municipalities in Brazil. This is an increase of 105 suspected cases since the last weekly update on 19 March. As of 29 March 2016, 944 of the cases have been confirmed to have microcephaly and/or other central nervous system findings suggestive of congenital infection. Of these cases, 130 have been confirmed positive for Zika virus by PCR. There have been 208 intrauterine or neonatal deaths reported among children notified to have microcephaly and/or central nervous system malformations. Of these, 47 cases were confirmed to have microcephaly and/or central nervous system malformations. One hundred and thirty-nine cases are still under investigation and 22 cases have been discarded.

 

Martinique: As of 31 March, two cases of microcephaly and one additional malformation case in a Zika positive patient have been reported in Martinique, according to ARS.