New information about Zika may become available before it can be included in this fact sheet. Please contact a MotherToBaby Service for additional information that may have become available.
In every pregnancy a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. This sheet talks about whether exposure to the Zika virus may increase the risk for birth defects over that background risk. This information should not take the place of medical care and advice from your health care provider.
What is Zika? How do people get the Zika virus?
Zika virus is usually spread by mosquito bites from infected mosquitos. Not all mosquitoes carry the Zika virus and not every person bitten by an infected mosquito will become infected. People who have the highest risk of getting the Zika virus are those who live in or who have traveled to an area with active Zika transmission from infected mosquitos.
The two main types of mosquitos that carry the Zika virus are Aedes aegypti and Aedes albopictus. These mosquitos can be found in many countries worldwide, including in parts of the United States (U.S.). Both mosquitos are commonly found in the southern half of the U.S., while Aedes albopictus mosquitos are also in the states across the Midwest and most of the northeastern states.
Other ways to become infected with the Zika virus include a pregnant woman passing the infection to her fetus, through sexual contact (vaginal, anal, oral and sharing of sex toys) and blood transfusions. At this time, it is unclear if the saliva from an infected person can infect another person, such as through deep kissing. There is no evidence that Zika is spread by coughing or sneezing.
What are the symptoms of Zika?
4 out of 5 people who are infected with the Zika virus do not have any symptoms. For those who develop symptoms, Zika virus commonly causes a mild flu-like illness that might include fever, rash, headache, joint and/or muscle pain and conjunctivitis (“pink eye”). Symptoms can begin 3-7 days after being infected and can last for several days to a week.
How is Zika treated?
There is no cure, medication or vaccine specific for Zika. Symptoms are treated by relieving fever, headache, joint pain, pink eye, and any other symptoms that might develop.
How can I protect myself from the Zika virus?
The best way to prevent infection of the Zika virus is to avoid traveling to areas of active Zika transmission. For a list of areas with active Zika transmission, visit the Centers for Disease Control and Prevention (CDC) webpage Zika Travel Information.
Another way to protect yourself is to avoid mosquito bites. Use insect repellents approved by the Environmental Protection Agency (EPA), wear protective clothing (such as long sleeves and long pants and/or clothing treated with the insecticide permethrin), and remove standing water, which is where mosquitoes live and lay their eggs. When possible, air-conditioning or screens should be used to keep mosquitoes out of the home. For more information on prevention, visit the CDC webpage Zika Virus Prevention. MotherToBaby fact sheets are also available for DEET and Pesticides and Pregnancy.
Since the Zika virus may be spread through sexual contact, the use of protection during sex is recommended. This includes not having sex with a potentially infected partner and the correct use of male and female condoms and dental dams from start to finish every time you have sex with a partner who may be infected. For more information, visit the CDC webpage Protect Yourself During Sex.
I got bit by a mosquito in the United States. Could I now be infected with the Zika virus?
The CDC has identified local outbreaks in Florida. This may change in the coming months. For the most updated information, call MotherToBaby toll-free at 1-866-626-6847.
Is there a test that can tell if I have or have had the Zika virus?
Yes, there are tests available that can tell if someone has or has had the Zika virus. All decisions regarding testing should be decided between your healthcare provider and your local health department. Guidelines for testing pregnant women and their sexual partners can be found through the CDC webpage on Interim Guidance for Health Care Providers.
What if I am pregnant and test positive for Zika?
There are CDC recommendations for how healthcare providers should follow the baby’s growth and development for the rest of the pregnancy. These recommendations can be found in the Interim Guidelines for Healthcare Providers, and may include more frequent ultrasounds (called serial ultrasounds) every 3–4 weeks and prenatal diagnostic tests to look for Zika infection in the baby. It is important to remember that just because a pregnant woman tests positive for Zika, it does not mean her baby will have birth defects.
What if I am pregnant and Zika infection cannot be ruled out, even after being tested?
In these cases, the CDC recommendations are that serial ultrasounds should be considered. These recommendations can be found in the Interim Guidelines for Healthcare Providers. Talk with your healthcare provider to find out more about serial ultrasounds.
Can the Zika virus affect my pregnancy?
Yes. If a pregnant woman is infected with the Zika virus, there is a chance that the virus will cross the placenta and affect the growth and development of the pregnancy. Specifically, Zika virus infection during pregnancy can cause microcephaly (small head and brain) and other severe brain defects. Other abnormalities that have also been associated include miscarriage, eye defects, hearing loss, problems with limb movement and impaired growth. The chance of a pregnancy developing birth defects is unknown, and research is ongoing. It is not yet known if it matters when in pregnancy Zika virus infection occurs.
If I tested positive for Zika, can the baby be checked for Zika virus infection at birth?
Yes. The CDC recommends that after birth, blood from babies born to mothers with confirmed or possible Zika virus infection be tested. More details for these recommendations can be found in the Interim Guidelines for Healthcare Providers webpage. Discuss the testing options for your baby with your healthcare provider.
Can I breastfeed if I have the Zika virus?
At this time, the CDC has not identified any cases of Zika virus infection of infants through breast milk. Evidence still suggests that the benefits of breastfeeding outweigh any potential risks associated with Zika virus infection through breastfeeding. Be sure to talk to your health care provider about all your breastfeeding questions.
If I am pregnant and I or my partner are considering travel to, or have already traveled to areas with local Zika transmission, what are the recommendations?
The CDC is recommending that pregnant women and their sexual partners avoid travel to areas where locally acquired cases of Zika have been reported. If travel cannot be avoided or if you live in one of these areas, follow the guidelines for prevention, which are found on the CDC Prevention webpage.
Men and women who have or will travel to areas with local Zika transmission should follow the recommendations for sex with a pregnant partner. These are found the CDC webpage Protect Yourself During Sex. Pregnant women and their sexual partners who have traveled to or live in one of these should talk to their healthcare provider about being tested for Zika.
What if I had sex with someone who is infected with the Zika virus or has been in an area where Zika is active?
A person who has Zika can pass it to their partner during sex. That is why it is important to protect yourself if your partner has potentially been exposed to the Zika virus. The CDC is recommending that partners of pregnant women use condoms correctly every time for vaginal, oral and anal sex or do not have sex with a potentially infected partner for the rest of the pregnancy. Visit the CDC webpages Women & Their Partners Who are Thinking about Pregnancy or Pregnant Women for more details.
I may have been exposed to the Zika virus. What can I do to prevent spreading Zika to other people?
It is very important to avoid being bitten by mosquitos. A mosquito who bites a person who has Zika is now infected with the Zika virus, too. This means that this infected mosquito can then bite and infect other people. This is how local transmission of the virus happens. To lower the chance of being bitten by a mosquito, people who have Zika should use insect repellent for three weeks after symptoms start. Guidelines for prevention can be found at Prevention webpage.
Are there other health problems that having Zika virus can cause?
Yes. While rare, people who have been infected with Zika virus have a small increased risk for developing Guillain-Barré syndrome (GBS). GBS is a condition that affects a person’s nervous system, leading to weakness or can cause a person to not be able to move certain parts of their body (called paralysis). While uncommon, GBS can sometimes affect the muscles that control breathing. Symptoms of GBS can last a few weeks to several months. Most people who develop GBS completely recover, but there are some who have permanent nerve damage.
Where can I get more information on the Zika virus?
Additional information can be found at:
- The WHO: http://www.who.int/mediacentre/factsheets/zika/en/
- PAHO: http://www.paho.org/hq/index.php?option=com_content&view=article&id=11585&Itemid=41688&lang=en
- Deet: https://mothertobaby.org/fact-sheets/deet-nn-ethyl-m-toluamide-pregnancy/pdf/
- Pesticides and Pregnancy: https://mothertobaby.org/fact-sheets/pesticides-pregnancy/pdf/
- From the CDC:
- Zika Virus Prevention: http://www.cdc.gov/zika/prevention/index.html
- Zika Travel Information: http://wwwnc.cdc.gov/travel/page/zika-information
- Prevention: http://www.cdc.gov/zika/prevention/index.html
- Protect Yourself During Sex: http://www.cdc.gov/zika/prevention/protect-yourself-during-sex.html
- Women & Their Partners Who are Thinking about Pregnancy: http://www.cdc.gov/zika/pregnancy/women-and-their-partners.html
- Pregnant Women: http://www.cdc.gov/zika/pregnancy/protect-yourself.html
- Interim Guidelines for Healthcare Providers: http://www.cdc.gov/mmwr/volumes/65/wr/mm6529e1.htm?s_cid=mm6529e1_e