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Zika virus: What you need to know

If you are concerned or have questions about the Zika virus

We have many users in countries affected by the Zika virus, or who are planning to travel to those countries. There’s a lot of confusing news reports and misinformation about the topic, so we wanted to provide a clear and science-based overview for you. New information is coming out every day so be sure to check reliable, recent reports for the most up-to-date information.

What is Zika?

Zika is a virus that, until last year, was not considered to be a big concern. It was first discovered in the 1940s and until 2007 there had only been 14 documented cases. That’s all recently changed, as the virus has been “spreading explosively,” according to the World Health Organization (WHO). Several regions of the world have been affected, especially Latin America, with the highest number of suspected cases in Brazil. Zika poses serious threats to unborn babies and, in addition to mosquitos, can be spread through sexual transmission and blood. On February 1st of 2016, the WHO named Zika a public health emergency.

Only about 1 in 5 people with Zika will have symptoms. When they do occur, they show up between 3–12 days after infection. Symptoms are usually mild and include a fever, a rash, muscle and joint pain, inflammation in the eye (conjunctivitis) and a headache. Research suggests that the virus usually leaves the blood within a week, but may last longer in semen. The infection can also make someone more likely to develop other serious conditions, like Guillain-Barré. Guillain-Barré is a neurological condition that can cause muscle weakness and paralysis lasting weeks to years. A vaccine or treatment for the Zika virus hasn’t yet been developed.


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Risks for pregnancy and infants

The Zika virus is especially concerning for people who are pregnant. Infection during pregnancy is linked to miscarriage and serious birth defects, especially microcephaly, a condition where a baby’s brain doesn’t develop properly, making their head visibly small. A study published on March 10, 2016 showed that about 1 in 3 fetuses developed microcephaly after the pregnant person became infected. In Brazil, several thousand new cases of microcephaly are being investigated.

There’s no evidence that Zika has any impact on a pregnancy or fetus after the virus has left the body, but the USA’s Center for Disease Control (CDC) is advising that symptomatic people wait at least 8 weeks after the appearance of their symptoms before becoming pregnant. The same is being advised for asymptomatic people who recently travelled to a Zika-affected country.

Some countries are advising people to avoid pregnancy altogether until the virus has been controlled. This is much more difficult for people with limited access to family planning education, condoms, hormonal contraception and abortion services.

Small amounts of the virus have been found in breastmilk, but the CDC advises people to continue breastfeeding. There hasn’t been evidence of a baby being infected through breastmilk, and the benefits of breastfeeding currently outweigh any theoretical Zika risks for babies.

Pregnant people who live in affected areas can be tested for the Zika virus throughout their pregnancy. This happens through regular fetal ultrasounds and sometimes blood tests. Of those who have had Zika during pregnancy, an amniotic fluid test may also be done, when available. Pregnant people who have returned from travel to Zika-affected areas, but who have no symptoms, may be offered testing for between 2–12 weeks after their return.

Sexual transmission of Zika

In early March, the WHO released a statement stating sexual transmission of the Zika virus was more common than they had previously thought. The confirmed cases, some in the USA, are thought to involve symptomatic men who passed the virus to their partner. It’s not known whether asymptomatic men can also spread the virus sexually, or how long the virus can last in semen. It’s suspected that Zika remains in semen longer than in blood. On March 25th, the CDC released specific suggestions for timeframes and safe sex practices (including oral sex) to prevent transmission of the virus in people who are in or have recently traveled to Zika regions. Suggestions have been made for people who’ve had Zika symptoms as well as those who are asymptomatic.

Precautions to take

People who are in, or traveling to, Zika-affected areas can take precautions to minimize their risk. Avoiding exposure to mosquitoes is most important. This might mean wearing protective clothing, using nets, closing windows without screens and staying away from areas with standing water when possible. Insect repellent can also be used, even by people who pregnant. Just make sure the repellent is safety-approved and follow the directions for use.

People who are pregnant, or planning on becoming pregnant are being advised to limit their exposure to the virus as much as possible.

The latest information

New information is coming all the time as the world learns more about this virus. If you live or may be traveling to an affected area, be sure to check for updates regularly. As of March 16, there have been over 250 travel-related cases of Zika in the USA, 6 of which were sexually transmitted.

If you are concerned or have questions about Zika, you can also contact our support team. While we cannot provide medical advice, we will do our best to direct you to the latest and most reliable information.

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