World: Zika virus, Microcephaly and Guillain-Barré syndrome Situation Report, 8 December 2016

KEY UPDATES

• Countries and territories reporting mosquito-borne Zika virus infections for the first time in the past week:
  • None
    
• 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:
  
  • Nicaragua
    
• Countries and territories reporting Guillain-Barré syndrome (GBS) cases associated with Zika virus infection for the first time in the past week:
  • None
    
• On 1 December, the United Kingdom of Great Britain and Northern Ireland reported the first case of person-to-person transmission of Zika virus. The case had no history of travel outside the country in the six months prior to symptom onset. The partner of the case had recently travelled to areas which have reported recent Zika virus circulation.

ANALYSIS

• Overall, the global risk assessment has not changed. Zika virus continues to spread geographically to areas where competent vectors are present. Although a decline in cases of Zika infection has been reported in some countries, or in some parts of countries, vigilance needs to remain high.

SITUATION

• Seventy-five countries and territories (Fig. 1, Table 1) have reported evidence of mosquito-borne Zika virus transmission since 2007 (69 with reports from 2015 onwards), of which:

  • Fifty-eight with a reported outbreak from 2015 onwards (Fig. 2, Table 1).
  • Seven with having possible endemic transmission or evidence of local mosquito-borne Zika infections in 2016.
  • Ten with evidence of local mosquito-borne Zika infections in or before 2015, but without documentation of cases in 2016, or with the outbreak terminated.

• Thirteen countries have reported evidence of person-to-person transmission of Zika virus (Table 2).

• Twenty-nine countries or territories have reported microcephaly and other CNS malformations potentially associated with Zika virus infection, or suggestive of congenital infection (Table 3). Nicaragua is the latest country to report two cases of microcephaly potentially associated with Zika virus infection.

• Twenty countries or territories have reported an increased incidence of GBS and/or laboratory confirmation of a Zika virus infection among GBS cases