Zika Virus

Zika is a viral illness that you can get from certain types of mosquitoes. Most people don’t know they have it or have very mild symptoms. If you get infected while pregnant, the virus can prevent the fetal brain from developing properly. This can lead to severe health conditions.

The mosquitoes that carry Zika are found in many parts of the world. Zika spreads in Mexico and parts of Central America, South America, Africa, and South and Southeast Asia. In 2015 and 2016, there was a large outbreak in the Americas. During this time, mosquito-borne Zika spread in Florida and Texas. Some U.S. citizens who had traveled to Central and South America also had the illness.

Symptoms of Zika virus infections

Most people don’t have symptoms. If you do, they could include:

• Fever
• Headache
• Joint pain
• Redness in the whites of your eyes
• Rash (possibly itchy) that’s a mix of raised and flat red or discolored areas of skin

Zika causes

A type of flavivirus (an RNA virus usually spread by mosquitoes) causes Zika infections. Zika virus can spread in many ways, including:

• Mosquitoes: The most common way to get Zika is through the bite of Aedes aegypti and Aedes albopictus mosquitoes. They live in many parts of the world, including the U.S. They spread Zika when they bite someone who’s infected and then bite someone else.
• Vertical transmission: If you’re pregnant, the Zika virus can pass through the placenta to the fetus. Zika can cause serious congenital conditions.
• Sexual contact: The virus can spread to other people through oral, anal or vaginal sex. It can stay in body fluids, like semen, for weeks to months after an infection, even if you never had symptoms or your symptoms have gone away.

Rarely, Zika virus has been transmitted through blood transfusions.

Complications

A small number of people with Zika develop Guillain-Barré syndrome (GBS). GBS is an autoimmune disorder that can cause weakness and paralysis. Most people recover from GBS in a few weeks to a few months.

If you’re pregnant and infected with Zika, the virus can also infect the fetus and interfere with its development. About 1 in 20 babies born to someone infected with Zika have congenital (present at birth) conditions. Some of these can be fatal. They include:

• A head that's smaller than average (microcephaly): Microcephaly can mean your child’s brain didn’t develop properly.
• Congenital Zika syndrome: This is a combination of conditions that your child is born with. These include severe microcephaly, a partially collapsed skull, a reduced amount of brain tissue, eye damage, joint issues and excessive muscle tone.
• Improper brain development: This includes neural tube defects, an absence of brain folds (lissencephaly), buildup of fluid on their brain (hydrocephalus), missing brain structures, brain atrophy and other issues.
• Cerebral palsy: This condition affects your child’s coordination and ability to control their muscles.
• Vision or hearing problems: Zika can cause irreversible damage to vision and hearing.
• Low birth weight: Low birth weight can cause long-term health problems. These include learning differences, developmental delays, heart disease and diabetes.

How doctors diagnose a Zika virus infection

A healthcare provider diagnoses Zika by looking for signs of the virus in your blood or pee (urine). Your provider will usually only test for Zika if you’ve been to a place with risk for the virus and you have symptoms. Make sure to let them know if you or a sexual partner has traveled recently.

How is Zika treated?

There isn't a specific medication that treats or cures Zika. Your provider can help you manage your symptoms and recommend ways to keep from spreading the virus to others. If you’re pregnant and test positive for Zika, your pregnancy care provider will help you manage your symptoms safely.

When should I see my healthcare provider?

See a healthcare provider if you have Zika symptoms and you:

• Have traveled to an area with a risk of Zika
• Live where there’s currently an outbreak
• Have a sexual partner who’s at risk for Zika, even if they don’t have symptoms

What can I expect if I have Zika?

Symptoms of Zika most often get better on their own. If you’re pregnant, your pregnancy care provider will monitor you and the pregnancy closely. It might be helpful to remember that most babies born to someone with Zika don’t have Zika-related conditions.

You can pass Zika virus through sex for several weeks longer than through mosquito bites. It stays in semen longer than vaginal fluid. There are steps you can take to avoid spreading Zika to others:

• For women with Zika, use condoms or don’t have sex for two months after your symptoms start.
• For men with Zika, use condoms or don’t have sex for three months after your symptoms start.
• Avoid getting bitten by mosquitoes for at least three weeks after your symptoms start. Wear bug spray and keep exposed skin covered.

Does Zika virus go away?

Zika virus infections usually go away on their own. Congenital conditions that Zika has caused are lifelong.

If you’re traveling to or live in an area with Zika, you can take steps to reduce your risk of getting or spreading the virus:

• Cover exposed skin with clothing and wear EPA-registered insect repellant. Sleep indoors in a room with screens in the windows or under a mosquito bed net.
• Avoid getting mosquito bites for at least three weeks after you return from travel.
• Use a condom or avoid oral, anal and vaginal sex for three months after returning, even if you don’t have symptoms. This is true even if you have sex with the same partner every time. Don’t share sex toys with others, as they can spread Zika, too.

If you’re pregnant or plan on becoming pregnant, take extra precautions:

• Avoid traveling to areas with Zika while pregnant or trying to become pregnant.
• If you travel to an area with a risk of Zika while pregnant, let your pregnancy care provider know and keep an eye out for symptoms.
• If there’s an outbreak where you live while you’re pregnant, take precautions to avoid mosquito bites and use condoms during sex.
• Consider waiting to get pregnant if you or your partner live in or have recently travelled to an area with a Zika outbreak, or if either of you have been diagnosed with Zika. Current guidelines suggest it’s safest to wait two months (for women) to three months (for men) to have sex after traveling or the start of your symptoms.