Epidemiological update: Outbreaks of Zika virus and complications potentially linked to the Zika virus infection, 23 March 2016

​New developments since the last epidemiological update published on 10 March 2016

Since last week, one new country, Vietnam, has reported autochthonous transmission. According to a press release by the Ministry of Health, Zika virus infection was diagnosed in an Australian traveller who had visited Vietnam between 26 February and 6 March 2016.

Madeira: On 22 March, local health authorities in Madeira reported two imported cases of Zika virus infection from Brazil. One of the cases is under investigation for potential sexual transmission.

Martinique: Media quoting the Ministry of Health, reported a suspected case of microcephaly linked with Zika virus infection.

Panama: On 18 March, the Ministry of Health reported a case of Zika congenital syndrome in a new-born baby that died on 17 March.

As of 24 March 2016, six countries have reported locally acquired infection in the absence of any known mosquito vectors, probably through sexual transmission: Argentina, France, Italy, New Zealand, Portugal (the Autonomous Region of Madeira) and the United States of America.

Detailed epidemiological situation

As of 23 March 2016, autochthonous cases of Zika virus infection have been reported from 43 countries and territories worldwide in the past two months (see Table 1 and Figure 1). Forty-five 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 23 March 2016

EU/EEA and EU Outermost Regions and Territories

As of 23 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 23 March 2016, ECDC has recorded 302 cases imported into 17 EU/EEA countries. In addition, one confirmed case has been published following diagnosis in a Slovenian hospital. Nineteen cases are among pregnant women.
 
Several of the EU’s Outermost Regions and Territories continue to report autochthonous transmission.
 
Martinique: As of 24 March 2016, 14 320 suspected cases have been reported, an increase of 1 760 during the past week.
 
French Guiana: As of 24 March 2016, 2 770 suspected and 210 laboratory-confirmed cases have been reported, an increase of 516 suspected and 15 laboratory-confirmed cases during the past week.
 
Guadeloupe: As of 24 March 2016, 794 suspected and 134 laboratory-confirmed cases have been reported, an increase of 44 suspected and 30 laboratory-confirmed cases during the past week.
 
Saint Martin: As of 24 March, 154 suspected and 10 laboratory-confirmed cases have been reported, this is an increase of 30 suspected and six laboratory-confirmed cases during the past week.

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

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 19 March 2016, there have been 6 671 suspected cases of microcephaly from 1 266 municipalities across Brazil. This is an increase of 191 suspected cases since the last weekly update on 12 March. As of 19 March 2016, 907 of the cases have been confirmed to have microcephaly and/or other central nervous system findings suggestive of congenital infection. Of these cases, 122 have been confirmed positive for Zika virus by PCR.
 
There have been 198 intrauterine or neonatal deaths reported among children notified to have microcephaly and/or central nervous system malformations. Of these, 46 cases were confirmed to have microcephaly and/or central nervous system malformations. One hundred and thirty cases are still under investigation and 22 cases have been discarded.
 
USA: On 21 March, WHO reported two cases of Guillain-Barré syndrome (GBS) with confirmed Zika virus infection in the USA. This is the first time that a country with no vector-borne transmission of Zika virus has detected patients with concomitant GBS and Zika virus infection.
 
Additional information may be found in the latest ECDC Risk Assessment (link).