Zika virus
Zika virus disease is mainly spread by mosquitoes. For most people it's a very mild infection and isn't harmful. It may be more serious for pregnant women, as there's evidence it causes birth defects. If you plan to travel to an affected area, seek travel advice before your trip.
About the Zika disease
Zika virus disease is caused by the Zika virus, which is usually spread to people through the bite of an infected mosquito (Aedes aegypti and Aedes albopictus).
The illness is usually mild with symptoms lasting up to a week. Many people do not have symptoms or will have only mild symptoms.
However, Zika virus infection during pregnancy can cause a serious birth defect called microcephaly and other severe brain defects.
People travelling to affected areas should seek travel health advice before their trip.
You can use the countries A-Z guide to check if the country you are visiting has a high risk, medium risk or low risk for Zika virus transmission.
Symptoms of Zika virus infection
Most people don't have any symptoms. If symptoms do occur, they are usually mild and last around two to seven days.
Commonly reported symptoms include:
- rash
- itching all over the body
- fever
- headache
- joint pain (with possible swelling, mainly in the smaller joints of the hands and feet)
- muscle pain
- conjunctivitis (red eyes)
- lower back pain
- pain behind the eyes
How you catch Zika virus infection
Most cases of Zika virus disease are spread by infected mosquitoes biting humans.
Unlike the mosquitoes that spread malaria, affected mosquitoes (the Aedes mosquito) are most active during the day, especially during mid-morning, then late-afternoon to dusk.
There have been a few reports of Zika virus being passed on through sexual intercourse, although the risk is thought to be low.
Reducing your risk of Zika virus infection
Before travelling, seek up-to-date travel health advice for your destination, available from:
If you need vaccinations or medication to protect you from malaria, check your vaccination status and discuss what medication is suitable for you, with your GP, practice nurse or a travel clinic.
Ideally, this should be at least four to six weeks before you go.
To reduce your risk of infection, you should avoid being bitten by an Aedes mosquito.
The most effective bite prevention methods, which should be used during daytime and night-time hours, include:
- using insect repellent that contains DEET (N, N-diethyl-meta-toluamide) on exposed skin, after sunscreen has been applied - DEET can be used by pregnant or breastfeeding women in concentrations up to 50 per cent, and in infants and children older than two months but should not be used on babies younger than two months
- wearing loose clothing that covers your arms and legs
- sleeping under a mosquito net in areas where malaria is also a risk
Advice for pregnant women
Zika virus infection is a cause of birth defects. This includes microcephaly (this means the baby will have an abnormally small head and can be associated with abnormal brain development). This is also known as congenital Zika syndrome.
It is therefore recommended that pregnant women postpone non-essential travel to areas with active Zika transmission until after pregnancy.
Discuss your travel plans with your GP, practice nurse or a travel clinic. If travel is unavoidable, then you should take extra care to avoid being bitten by mosquitoes.
If you and your partner are currently in an area with active Zika virus transmission, make sure you use condoms during vaginal, anal and oral sex while travelling and while pregnant.
If you are pregnant and have recently returned from an area with active Zika virus transmission, see your GP or midwife. You should tell where you have been, even if you have not been unwell.
Your midwife or hospital doctor will discuss the risk with you and can arrange an early ultrasound scan of your baby to monitor growth.
If there are any issues, you will be referred to a specialist for further monitoring.
Advice for women trying to get pregnant
If you are trying to get pregnant, discuss your travel plans with your GP, practice nurse or travel clinic. You should take extra care to avoid being bitten by mosquitoes.
It is recommended that you avoid becoming pregnant while travelling to an area with active Zika virus transmission, and for eight weeks after you return home.
It is also recommended you take folic acid supplements for 28 days before trying to get pregnant.
If you have experienced Zika symptoms within two weeks of returning home, it is recommended that you wait at least eight weeks after full recovery before you try to get pregnant.
If your partner (male or female) has travelled to an area with active Zika virus transmission, you should use effective contraception to prevent pregnancy and condoms during vaginal, anal and oral sex to reduce the risk of sexual transmission. These measures should be taken during travel and:
- for six months after their return home, even if they have no Zika symptoms
- for six months following the start of their symptoms, if they do experience Zika symptoms or a Zika virus infection has been confirmed by a doctor
How Zika virus infection is treated
There is no specific treatment for Zika virus symptoms.
Drinking plenty of water and taking paracetamol may help relieve symptoms.
If you feel unwell after returning from a country that has malaria as well as active transmission of Zika virus, you should seek urgent (same day) advice to help rule out a malaria diagnosis.
If you continue to feel unwell and malaria has been shown not to be the cause, seek medical advice.
Zika virus and blood donation
If you have travelled to areas with active Zika virus transmission, you should declare this if wanting to donate blood. It is recommended that you wait 28 days before donating blood, after returning.
Advice on blood donation is available at:
Zika virus and Guillain-Barré syndrome
Zika virus is a cause of Guillain-Barré syndrome (GBS), a serious condition of the nervous system.
The risk of developing GBS following a Zika virus infection is currently unknown, but thought to be very low.
More useful links
- Foreign travel advice
- National Travel Health Network and Centre website
- Holiday and travel advice (Public Health Agency website)
The information on this page has been adapted from original content from the NHS website.
For further information see terms and conditions.