What is Zika?

Zika is caused by a virus, which is spread by the Aedes mosquito. Zika can also be passed on during sex. If you’re travelling to an area with a high Zika risk, you need to take precautions such as using an approved mosquito repellent and using a mosquito net. If you’re pregnant then you should avoid travel to Zika risk areas entirely as Zika can harm your unborn child. There is no treatment for Zika, so it’s important to try and avoid getting it in the first place.  

What causes Zika?

Zika can be spread through:

  • Mosquito bites: Zika is most commonly transmitted via the bite of an infected Aedes Aegypti mosquito. This mosquito is found in tropical regions and they usually bite during the day, primarily in the  early morning and late afternoon/evening.
  • Mother to child: Pregnant women can pass on the virus to their unborn child. This can happen during pregnancy or childbirth. How commonly this type of transmission occurs is not currently known. The Zika virus has also been found in breast milk, although actual transmission through breast milk hasn’t been proven yet and the World Health Organisation recommends the benefits of breastfeeding outweigh any potential risk. Babies infected with Zika may develop symptoms such as a fever, rash or eye infection.
  • Sex: Since people often only have mild symptoms or no symptoms, they don’t necessarily know they’re infected. Zika patients are contagious before the symptoms start to show. While you’re in a high risk area, practise safe sex by using condoms and dental dams and avoid sharing sex toys. After you return you still need to practice safe sex using condoms for at least 8 weeks if you are female or at least 6 months if you are male to prevent transmission of Zika.
  • Blood transfusions: In most countries where the risk of Zika is high, blood transfusions are routinely screened for the Zika virus. If you are in a country where there is a risk of Zika and require blood transfusions there could be a risk of infection if blood samples are not tested.

What are the symptoms of Zika?

Many people infected with the Zika virus won’t have any symptoms or will only have mild symptoms. The most common symptoms of Zika are:

  • Fever
  • Rash
  • Headache
  • Joint pain - there might also be some swelling like in the joints of the hands and feet
  • Red eyes
  • Conjunctivitis
  • Lower back pain
  • Muscle pain

Symptoms can last for a few days to a week. Although the disease is usually mild, it can, in rare cases, cause serious complications such as Gullain-Barre Syndrome and be fatal. Once you’ve had Zika, you’re likely to be protected from future Zika infections as your immune system will be able to identify and fight the virus.

If you’re pregnant, Zika can cause a serious birth defect called microcephaly – this is when the baby’s head is smaller than usual, which can be a sign that the brain hasn’t developed normally.

In which parts of the world does Zika occur?

The risk of getting Zika depends on the altitude of the place you’re travelling to (ie how far above sea level you are). The Aedes species mosquitoes that spread Zika usually don’t live at high altitudes of more than 2,000 meters which is why Zika is less common at high altitudes.

The regions where Zika has been reported so far are Central and South America, North America, the Caribbean, Asia, Australasia and Africa. However, risk levels are always changing.

Zika does not occur in the UK.

How is Zika treated?

There is no treatment for Zika, but the following may help alleviate symptoms:

  • Rest
  • Drink water to prevent dehydration
  • You can relieve fever and pain with medication like paracetamol
  • If you feel unwell after returning from a country that has malaria as well as Zika virus, you should seek urgent and immediate advice to help rule out a malaria diagnosis.
  • If you’re already taking medication for another condition, then talk to your doctor or pharmacist  before taking any other medications.
  • If you’re not getting well, or are concerned, then visit your doctor.
  • Don’t take aspirin and/or any other non-steroidal anti-inflammatory drugs until you have been diagnosed by a doctor - dengue fever can have similar symptoms and these medications can increase the risk of bleeding

What can you do to prevent Zika?

To reduce your risk of Zika, you should try to avoid being bitten by an Aedes mosquito. The most effective bite prevention methods include:

  • Using insect repellent that contains at least 20% DEET (diethyltoluamide, the most common active ingredient in insect repellents) on exposed skin, after sunscreen has been applied. DEET can be used by pregnant or breastfeeding women in concentrations up to 50%, and in infants and children older than two months
  • Wear loose, long-sleeved shirts and long trousers to cover your arms and legs.
  • Treat your clothing with permethrin or buy them already treated.
  • Insect repellents shouldn’t be used on babies younger than 2 months. If they contain certain chemicals like oil of lemon eucalyptus or para-menthane-diol, then they also shouldn’t be used on children younger than 3 years.
  • Use door screens inside, and sleep under a mosquito bed net if you’re not in an air conditioned or screened room, or are sleeping outdoors.
  • Don’t allow there to be standing water around or within the place you’re staying.
  • Either use condoms or don’t have sex during travel to higher risk regions and for at least 8 weeks after if you are female or, if you are male for at least 6 months after.

If you plan to travel to an affected area, seek travel health advice before your trip from your GP. The travel advice you receive will be tailored to you depending on the country you’re visiting and its associated Zika risk status, and your own health status.