Emergencies preparedness, response

Information for travellers visiting Zika affected countries

Updated 19 April 2017

Zika virus is primarily transmitted to people through the bite of an infected Aedes mosquito. Zika virus can also be transmitted through sex.

Based on available evidence, WHO has issued no general restrictions on travel or trade with countries, areas and/or territories with Zika virus transmission.

However, WHO is advising pregnant women not to travel to Zika-affected areas in categories 1 and 2 in the country classification table.

  • Category 1: Area with new introduction of Zika virus since 2015 or area where the virus has been re-introduced, with ongoing transmission.
  • Category 2: Area either with evidence of Zika virus circulation before 2015 OR with ongoing transmission but the area does not satisfy the criteria for category 1 or 3. Areas in category 2 may also experience an outbreak of Zika.
  • Category 3: Area with interrupted transmission but with potential for future transmission.
  • Category 4: Area with established Aedes aegypti mosquitoes but no known documented past or current transmission.

This advice is based on the increased risk of microcephaly and other congenital malformations in babies born to pregnant women infected with Zika virus. Microcephaly is a condition where a baby is born with a small head or the head stops growing after birth.

As a precautionary measure, some national governments may make public health and travel recommendations to their own populations, based on their assessment of the available evidence and local risk factors.

Before travelling to Zika-affected areas in categories 1 and 2

Risk of infection may vary significantly between areas of a given country or region and may change over time. Travellers are advised to check with their doctor and local and national health authorities to seek up-to-date advice on potential risk associated with their specific travel itinerary and any underlying medical conditions and appropriate measures to reduce the possibility of exposure to mosquito bites and of sexual transmission of Zika virus.

While in Zika-affected areas in categories 1 and 2

Men and women should practice safer sex (including the consistent use of condoms) or abstinence to prevent Zika virus infection, human immunodeficiency virus (HIV), other sexually transmitted infections and unwanted pregnancies.

To prevent mosquito bites during the trip, travellers are advised to:

  • wear clothing - preferably light coloured - that covers as much of the body as possible;
  • use insect repellents that contain DEET (diethyltoluamide), IR 3535 ((3- [N-butyl-N-acetyl], aminopropionic acid ethyl-ester) or KBR3023 (also called Icaridin or Picaridin). Repellents may be applied to exposed skin or to clothing and must be used in strict accordance with the label instructions; if repellents and sunscreen are used together, sunscreen should be applied first and the repellent thereafter;
  • use physical barriers such as regular or mesh screens or insecticide treated netting materials on doors and windows , or closing doors and windows; and
  • sleep under mosquito nets, especially during the day, when Aedes mosquitoes are most active.

Upon return home

To prevent the onward transmission of Zika and adverse pregnancy and fetal outcomes, all returning travellers from Zika-affected areas in categories 1 and 2 should practice safer sex, including through the correct and consistent use of condoms, or consider abstaining from sex for at least 6 months.

Travellers returning home should also continue to use insect repellent for at least three weeks to avoid being bitten and potentially spreading the infection to other people through mosquito bites.

Sexual partners of pregnant women should practice safer sex or abstain for at least the duration of the pregnancy.

This page links all WHO information to its response on the Public Health Emergency of International Concern.