Zika virus is a mosquito-borne infection that is usually mild but can cause serious birth defects if a woman is infected during pregnancy. There is no vaccine, so prevention relies on mosquito-bite avoidance, careful pregnancy and travel planning, and avoiding sexual transmission.
How it spreads
Mainly through the bite of infected daytime-biting Aedes mosquitoes; also through unprotected sex and from a pregnant woman to her unborn baby.
Where it occurs
Tropical and subtropical regions including Central and South America, the Caribbean, sub-Saharan Africa, South and Southeast Asia and some Pacific islands.
Main symptoms
Often none; when present, usually mild fever, itchy rash, joint and muscle pain, headache and red, sore eyes for a few days.
Who is most at risk
Pregnant women and their unborn babies face the most serious risk; couples planning a pregnancy also need particular care.
Is a vaccine available
No. There is no licensed Zika vaccine and no specific antiviral treatment, so prevention is the priority.
How to reduce your risk
Avoid mosquito bites throughout the day with repellent and covering clothing, and follow safer-sex and pregnancy-planning advice after travel.
Zika virus is a mainly mosquito-borne infection that is usually mild but can cause serious birth defects if a woman is infected during pregnancy. There is no vaccine, so travellers prevent it by avoiding daytime mosquito bites with repellent and covering clothing, and by following safer-sex advice after travel. Crewe Travel Clinic offers Zika risk assessment and bite-avoidance advice, with tailored guidance for those who are pregnant or planning a pregnancy.
Zika virus is a flavivirus spread mainly through the bite of infected Aedes mosquitoes, the same daytime-biting mosquitoes that transmit dengue and chikungunya. For most people the infection is mild or causes no symptoms at all, and serious illness in otherwise healthy adults is uncommon. The principal concern with Zika is its effect during pregnancy: infection in a pregnant woman can cross to the developing baby and cause congenital abnormalities, including microcephaly (an abnormally small head) and other neurological problems.
Following the large outbreaks across the Americas and the Pacific in 2015 and 2016, Zika transmission has continued at lower levels in many tropical and subtropical regions. Because the virus can also be passed on through sex and, rarely, from mother to baby, prevention involves more than avoiding mosquito bites alone. There is no vaccine and no specific antiviral treatment, so reducing the risk of infection is the most important step for travellers.
At Crewe Travel Clinic we provide up-to-date, individualised advice on Zika risk for your destination, with particular care for travellers who are pregnant, planning a pregnancy, or travelling with a partner who is or may become pregnant. A pre-travel consultation allows us to assess your itinerary against current TravelHealthPro country guidance and recommend appropriate precautions.
Zika virus is transmitted mainly by the bite of infected Aedes mosquitoes, which typically bite during the day, peaking in the early morning and late afternoon. The virus can also be passed on through unprotected sex with an infected person, and it can be transmitted from a pregnant woman to her unborn baby. Less commonly, it may be spread through blood transfusion. The virus can persist in semen for some time after infection, which is why protected sex or abstinence is advised for a period after travel to a risk area.
Around 4 in 5 people infected with Zika have no symptoms at all. When symptoms do occur they are usually mild and last a few days to a week, typically including a low-grade fever, an itchy rash, joint pain, muscle aches, headache and red, sore eyes (conjunctivitis). Severe illness requiring hospital care is rare. In a small number of cases Zika has been linked to Guillain-Barré syndrome, a temporary neurological condition. The most serious consequences occur when a woman is infected in pregnancy, as the virus can cause microcephaly and other birth defects in the baby.
Zika occurs across much of Central and South America, the Caribbean, sub-Saharan Africa, South and Southeast Asia and some Pacific islands. Risk is highest in tropical and subtropical regions where the Aedes mosquito is established. Many countries report ongoing low-level transmission rather than large outbreaks, and the risk in a particular destination can change, so current country-specific advice from TravelHealthPro (NaTHNaC) should always be checked before travel, especially for those who are pregnant or planning a pregnancy.
There is no vaccine against Zika virus, so prevention depends on avoiding mosquito bites and reducing the risk of sexual transmission. Travellers are advised to use an insect repellent containing 50% DEET on exposed skin, wear loose long-sleeved clothing and long trousers, and sleep in air-conditioned or screened accommodation, using a mosquito net where needed. Because the Aedes mosquito bites during the day, bite avoidance should be practised throughout daylight hours, not only at night. Pregnant women are generally advised to postpone non-essential travel to areas with Zika risk. Couples in which either partner has travelled to a risk area are advised to use condoms and to avoid conceiving for a defined period after returning; current TravelHealthPro guidance should be followed, and a pre-travel discussion at the clinic is recommended for anyone who is pregnant or planning a pregnancy.
Zika virus is spread mainly by the bite of infected Aedes mosquitoes, which bite during the day and peak in the early morning and late afternoon. Unlike malaria mosquitoes, they are active in daylight, so bite avoidance is needed throughout the day. The virus can also be passed on through unprotected sex and from a pregnant woman to her unborn baby, and rarely through blood transfusion.
As there is no vaccine, avoiding mosquito bites is the most important measure, alongside steps to prevent sexual transmission. Travellers are advised to use an effective insect repellent on exposed skin, cover up with loose long-sleeved clothing, and use screened or air-conditioned accommodation. Pregnant women are generally advised to postpone non-essential travel to areas with Zika risk, and couples should follow current advice on safer sex and pregnancy planning after travel.
Most people infected with Zika have no symptoms, and illness is usually mild and short-lived, lasting a few days to a week. Severe illness in healthy adults is uncommon. Anyone who is pregnant, or becomes unwell after travel to a Zika risk area, should seek medical advice. Pregnant women who have travelled to a risk area are advised to tell their midwife or doctor, even if they have felt well, so that monitoring can be arranged.
There is currently no licensed vaccine against Zika virus and no specific antiviral treatment. This makes prevention through mosquito-bite avoidance and safer-sex precautions essential, particularly for travellers who are pregnant or planning a pregnancy. A pre-travel consultation at Crewe Travel Clinic allows your destination to be reviewed against current TravelHealthPro guidance so that appropriate precautions can be recommended.
The following vaccinations can help protect against Zika Virus.
Book an appointment with our travel health team for tailored advice on protecting against Zika Virus.