Zika virus disease is mainly spread by mosquitoes. For most people it is a very mild infection and isn’t harmful.
However, it may be more serious for pregnant women, as there’s evidence it causes birth defects – in particular, abnormally small heads (microcephaly).
Zika outbreaks have been reported in the Pacific Islands, South and Central America, the Caribbean, Africa and parts of South and South East Asia.
If you plan to travel to an affected area, seek travel health advice before your trip. Travel advice is tailored to you and based on the level of risk (high, moderate, low) for the country you’re travelling to.
High-risk areas are where there are current outbreaks of Zika virus, or where there has been an increase in the number of cases acquired locally, through mosquito bites.
If you travel to an affected area, you can reduce your risk of catching the virus by using insect repellent and wearing loose clothing that covers your arms and legs.
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:
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 small number of reports of Zika virus being passed on through sexual intercourse, although the risk is thought to be low.
Scientists have concluded that there is enough evidence to show that Zika virus infection is a cause of birth defects, including 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.
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 high or moderate risk of Zika virus transmission, and for eight weeks after you return home. It is also recommended that 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 eight weeks after full recovery before you try to get pregnant.
If your male partner has travelled to an area with high or moderate risk of 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: