The World Health Organization (WHO) reports that the Zika virus has now spread through both South and Central America and expects 3-4 million people to be infected in 2016.
So what is the Zika virus and what steps can you take to protect yourself? Answers below.
What is the Zika virus?
The Zika virus is a mosquito-borne infection, which isn't harmful in most cases. However, it may be harmful for pregnancies, as it's been potentially linked to birth defects - specifically, abnormally small heads (microcephaly).
It was first detected in the Zika forest of Uganda in 1947, and has circulated in Africa and South and South East Asia without many documented outbreaks reported. In the last few years, Zika outbreaks have been reported in the Pacific region, and the virus has now spread to South and Central America, and the Caribbean. WHO has warned that Zika virus is likely to spread to all countries in the Americas where the climate is suitable for the affected mosquitoes. Currently, this is thought to be all the countries in the Americas (including the Caribbean) with the exception of Chile and Canada.
Zika virus and blood donation
As a precaution the NHS Blood and Transplant service has recommended that people who have travelled to countries where the Zika virus is active wait 28 days before donating blood.
If you want to know whether any recent foreign travel temporarily bars you from giving blood, you can call their National Contact Centre on 0300 123 23 23.
What symptoms does the virus cause?
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:
- a low-grade fever
- joint pain (with possible swelling, mainly in the smaller joints of the hands and feet)
- rash, which is sometimes itchy
- conjunctivitis (red eyes)
- eye pain
How does the Zika virus spread?
Most cases of the Zika virus are spread by infected mosquitoes biting humans. Unlike the mosquitoes that spread malaria, affected mosquitoes (the Aedes mosquito) are most active during the day (but especially during mid-morning and late afternoon to dusk).
There has been one case where Zika virus may have occurred through sexual intercourse and a small number of cases have occurred by transmission from an expectant mother to her unborn child via the placenta.
How do I reduce my risk of contracting the Zika virus?
Before travelling, seek travel health advice from your GP/practice nurse or a travel clinic ideally six to eight weeks before you go. Detailed travel health advice for your destination is also available from the National Travel Health Network and Centre (NaTHNaC) website or the Scottish travel health service fitfortravel.
To reduce your risk of infection with Zika virus, you should avoid being bitten by an Aedes mosquito. The most effective bite prevention methods, which should be used during daytime and nighttime hours, include:
- using insect repellent that contains N, N-diethyl-meta-toluamide (DEET) on exposed skin - the repellent is safe to use during pregnancy and should be applied to skin after sunscreen is applied
- wearing loose clothing that covers your arms and legs
- sleeping under a mosquito net in areas where malaria is also risk
What risks does the Zika virus pose in pregnancy?
There is evidence to suggest that pregnant women who contract the virus during pregnancy (at any trimester) may have an increased risk of giving birth to a baby with microcephaly (this means an abnormally small head and can be associated with abnormal brain development).
Current advice is that women who are pregnant or planning to become pregnant should discuss their travel plans with their doctor and if already pregnant to consider postponing travel to any region where a known outbreak of the Zika virus is occurring. If travel is unavoidable then they should take scrupulous insect bite avoidance measures.
Public Health England (PHE) provides regular updates about the current spread of the disease.
I am pregnant and have visited a country where there is an ongoing Zika virus outbreak. What should I do?
If you are pregnant and have a history of travel to a country where there is an ongoing Zika virus outbreak, see your GP or midwife and mention your travel history even if you have not been unwell. Your midwife or hospital doctor will discuss the risk with you and will arrange an ultrasound scan of your baby to monitor growth.
If you have experienced Zika symptoms either during or within two weeks of returning home, see your GP or midwife or mention your travel history. Your midwife or hospital doctor will discuss the risk with you and will arrange an ultrasound scan to measure your baby's growth and brain development. If there are any problems you will be referred to a specialist fetal medicine service for further monitoring. If you are still experiencing Zika symptoms your GP will arrange for you to have a blood test to check for Zika virus.
I am trying to get pregnant and have visited a country where there is an ongoing Zika virus outbreak. What should I do?
If you are trying to get pregnant and have a history of travel to a country where there is an ongoing Zika virus outbreak, see your GP or midwife and mention your travel history even if you have not been unwell. It is recommended that you take folic acid supplements for 28 days before trying to conceive.
If you have experienced Zika symptoms either during or within two weeks of returning home it is recommended that you wait at least six months after full recovery before you try to conceive.
Even if you have not been unwell, it is recommended that you wait at least 28 days after you return home from a country where there is an ongoing Zika virus outbreak before you try to conceive.
My partner has visited a country where there is an ongoing Zika virus outbreak. What should I do?
Sexual transmission of Zika virus has occurred in a small number of cases, but the risk of sexual transmission of Zika virus is thought to be very low. If your partner has travelled to a country where there is an ongoing Zika virus outbreak, condom use is advised:
- for 28 days after his return home if he had no Zika symptoms
- for six months following recovery if he experienced Zika symptoms or a Zika virus infection has been confirmed by a doctor
For advice on the options available to you on other methods of contraception, speak to your GP or community sexual health clinic.
What if I am worried that my baby has been affected by the Zika virus?
Speak to your midwife or doctor for advice. If you are still concerned after receiving assurances from your healthcare professional and feel anxious or stressed more than usual, you can ask your GP or midwife for referral to further counselling.
How is the Zika virus diagnosed and treated?
The Zika virus can be diagnosed with a blood test in people who are currently/actively displaying symptoms of Zika virus infection.
There is no specific treatment for the symptoms of the Zika virus. Drinking plenty of water and taking paracetamol may help relieve symptoms. The use of aspirin or non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen is not recommended, as there is a potential risk they could trigger excessive bleeding.
If you feel unwell on return form a country with an ongoing outbreak of Zika virus, but which also has malaria, you should seek urgent (same day) advice to help rule out a diagnosis of malaria.
If you remain unwell and malaria has been shown not to be the cause, seek medical advice.
The World Health Organization reports that the Zika virus has now spread through both South and Central America and expects three to four million people to be infected in 2016. So what is the Zika virus and what steps can you take to protect yourself?
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Public Health England. Zika virus: travel advice for pregnant women.
Royal College of Obstetricians and Gynaecologists. Q&As on Zika and pregnancy
Centers for Disease Control and Prevention. Zika-affected areas.
World Health Organization. Zika virus fact sheet.
Travel Health Pro. Zika virus - update and advice for travellers including pregnant women
European Center for Disease Prevention and Control (ECDC). Countries with local Zika transmission
Best use of medicines in pregnancy. Zika virus