What You Need to Know About the Zika Virus Outbreak

No vaccines or medicine yet exist to treat the pathogen
What You Need to Know About the Zika Virus Outbreak

Updated April 14, 2016

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By now you’ve heard a lot about the Zika virus. What do you need to know?

What is the Zika virus?

Zika is a pathogen that typically causes only mild symptoms. The Zika virus is most often transmitted through the bite of an infected Aedes mosquito, according to the Centers for Disease Control and Prevention (CDC). The mosquitoes become infected when they bite a person already infected with the virus.

It’s also been reported that the virus can spread through blood transfusion and sexual contact and from a mother already infected with the virus to her newborn around the time of birth. The CDC has issued guidelines on how to prevent sexual transmission of the virus.

The World Health Organization has said there is a strong scientific consensus that the Zika virus is associated with Guillain-Barre syndrome, in which the body attacks its own nerves, causing paralysis.

However, researchers don’t know everything about the Zika virus yet. No vaccine or medicine exists specifically to treat people with the virus, the CDC says, although it appears the first Zika vaccine candidate is on target to enter initial clinical trials in September.


Zika has been known to exist since 1947, but was long considered to be a minor disease that causes only mild illness.

Symptoms of the Zika virus can include fever, rash, joint pain or red eyes. Those infected with the virus usually experience symptoms within two to seven days after being bitten by an infected mosquito.

You can treat the symptoms by getting plenty of rest and fluids. Reduce fever and pain by taking acetaminophen.

The virus is out of the body of a sick person after about a week. Once you’ve been infected with the virus, you’re likely protected from future infections, the CDC says.

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Avoiding infection

The Zika virus is not spread through touch, coughing or sneezing. It is not contagious like the flu or a cold and people with the virus do not need to be isolated from others. The virus is sexually transmitted when a person is actively infected and showing symptoms.

Here are actions you can take to prevent the possibility of infection:

  • Avoid travel to a Zika-infected area. Consult your health care provider if you must travel.
  • If you must travel to an area with Zika virus, use mosquito repellant such as DEET, expose as little skin as possible when outside, and avoid being outside if possible.
  • If your partner has traveled to a Zika-infected area, avoid unprotected sexual intercourse and use a condom correctly and consistently for the time being. Your partner should be tested for the Zika virus.

Zika and birth defects

Medical evidence now shows Zika virus is a cause of microcephaly and other severe fetal brain defects, the CDC says in a report published in the New England Journal of Medicine.

No single piece of evidence provides conclusive proof that Zika virus infection causes microcephaly and other fetal brain defects, the report says. However, increasing evidence from a number of recently published studies and a careful evaluation using established scientific criteria supports its conclusions, the CDC says.

The CDC’s finding means that a woman who is infected with Zika during pregnancy has an increased risk of having a baby with these health problems.

“When the virus goes to the bloodstream it can pass to the baby and cause inflammation of the baby’s brain,” says infectious disease specialist Lucileia Johnson, MD.

However, the finding does not say that all women who have Zika virus infection during pregnancy will have babies with problems. Some infected women have delivered babies that appear to be healthy.

The CDC says it will launch further studies to determine whether is Zika is the cause of other damaging effects on the fetal brain and developmental problems. Since concerns about Zika’s effect on pregnancies first surfaced, the CDC has linked the virus to a broader array of birth defects. These include premature birth and blindness, and throughout a longer period of pregnancy than initially thought.

Health officials have suspected a link between Zika and birth defects since late last year after it was revealed that Brazil witnessed a 20-fold increase of microcephaly from 2014 to 2015.

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Microcephaly is a rare neurological disorder in which the circumference of the head is smaller than average for an infant’s size and age. Microcephaly often is associated with some degree of mental retardation. However, in 15 percent of the cases, the child has normal intelligence.

To date, there are no reports of infants getting Zika virus through breastfeeding, the CDC says. Because of the benefits of breastfeeding, mothers are encouraged to breastfeed even in areas where Zika virus is found.

Travel advisory

The CDC is advising women who are pregnant or thinking of becoming pregnant to avoid going to countries in South America, Central America, Mexico and the Caribbean, where the virus is rapidly spreading.

The potential geographic range of the mosquitoes transmitting the virus also reaches into the United States, with the Aedes aegypti species present in all or part of 30 U.S. states, the CDC says.

If you have traveled to an area affected by the Zika virus and are planning to get pregnant, whether through intercourse or in vitro fertilization, you should speak with your physician. This includes men as well, as Zika can be passed through semen.

Dr. Johnson says that pregnant women who may have been to any of these countries recently also should contact their physician.

“You have to seek professional advice,” Dr. Johnson says. “I would not panic. Just get tested if it’s going to bring you peace of mind.”

The CDC says that because the species of mosquitoes that spread Zika virus are found throughout the world, it is likely that outbreaks will occur in new countries.

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