The Zika virus is spread primarily through the bite of an infected mosquito. These are the same mosquitoes that spread other viruses like dengue and chikungunya. Only about one in five people infected with the Zika virus will feel sick. In those that do, symptoms are usually mild and can include fever, rash, joint pain and red eye.

Learn more about symptoms and diagnosis from the Centers for Disease Control and Prevention (CDC).

Many people infected with Zika virus won’t have symptoms or will only have mild symptoms. 

• The most common symptoms of Zika are fever, rash, joint pain, or conjunctivitis (red eyes). 
• Other common symptoms include muscle pain and headache. 
• The illness is usually mild with symptoms lasting for several days to a week.
• People usually don’t get sick enough to go to the hospital, and they very rarely die of Zika. For this reason, many people might not realize they have been infected.

The incubation period (the time from exposure to symptoms) for Zika virus disease is not known, but is likely to be a few days to a week. See your doctor or other healthcare provider if you are pregnant and develop a fever, rash, joint pain, or red eyes within 2 weeks after traveling to an area with Zika. Be sure to tell your doctor or other healthcare provider where you traveled.

Zika is primarily spread to people through the bite of infected Aedes mosquitoes. It can also be transmitted from a pregnant mother to her baby during pregnancy, though we do not know how often that transmission occurs.

Learn more about Zika transmission.

• Zika virus can be spread by a man to his sex partners.
• In known cases of sexual transmission, the men developed Zika virus symptoms. From these cases, we know the virus can be spread when the man has symptoms, before symptoms start and after symptoms resolve.
• In one case, the virus was spread a few days before symptoms developed.
• The virus is present in semen longer than in blood.

>>View the CDC's Interim Guidance for Prevention of Sexual Transmission of Zika Virus

People are contracting Zika in areas where Aedes mosquitoes are present, which include South America, Central America and the Caribbean. As the CDC notes, specific areas where the Zika virus is being transmitted are likely to change over time, so please check the CDC website for the most updated information.

Anyone who is living in or traveling to an area where the virus is found is at risk for infection.

There is no vaccine or specific medicine to treat Zika virus infections.

Treat the symptoms:

• Get plenty of rest.
• Drink fluids to prevent dehydration.
• Take medicine such as acetaminophen to reduce fever and pain.
• Do not take aspirin or other non-steroidal anti-inflammatory drugs.
• If you are taking medicine for another medical condition, talk to your healthcare provider before taking additional medication.

There may be a link between a serious birth defect called microcephaly—a condition in which a baby's head is smaller than expected—and other poor pregnancy outcomes and a Zika infection in a mother during pregnancy. While the link between Zika and these outcomes is being investigated the CDC recommends that you take special precautions if you fall into one of these groups:

If you are pregnant (in any trimester):

• You should consider postponing travel to any area where the Zika virus is active.
• If you must travel to an active region, talk to your doctor first and follow the steps to prevent mosquito bites during your trip.
• If you are trying to become pregnant:
• Before you travel, talk to your doctor about your plans to become pregnant and the risks posed from infection.

For more information, please visit the CDC's resources:

• Thinking About Pregnancy
• Pregnancy Questions & Answers
• Contraceptition to Prevent Unintended Pregnancy during the Zika Outbreak
• Contraceptive Use of Nonpregnant and Postpartum Women

Families of newborns affected by Zika virus (Zika) may be overwhelmed, worried, and unsure of next steps in caring for their baby.  A baby affected by Zika virus may be born with significant health issues, like microcephaly. Others may not have apparent symptoms at birth, but may develop them over time.

For more information, please visit the CDC web page for Families of Newborns Affected by Zika.

Right now, there is no vaccine to prevent this disease. The best way to prevent diseases by mosquitoes is to protect yourself from getting bitten. Here’s how:

• Wear long-sleeved shirts and long pants.
• Stay in places with air conditioning or that use window, door screens, and netting to keep mosquitoes outside.
• Use Environmental Protection Agency (EPA)-registered insect repellents. All EPA-registered insect repellents are evaluated for safety and effectiveness.
• Treat clothing and gear with permethrin or purchase permethrin-treated items.
• Sleep under a mosquito bed net if you are overseas or outside and are not able to protect yourself from mosquito bites.

You can get a more in-depth explanation of prevention measures from the CDC.

• The U.S. mainland does have Aedes species mosquitoes that can become infected with and spread Zika virus. 
• U.S. travelers who visit a country where Zika is found could become infected if bitten by a mosquito.
• View Zika cases reported in the United States

Florida

The Florida Department of Health has identified two areas of Miami-Dade County where Zika is being spread by mosquitoes. In addition to the previously identified area in the Wynwood neighborhood, there is now mosquito-borne spread of Zika virus in a section of Miami Beach. >>Learn More