Zika: What women need to know

Zika: What women need to know

April 2016


As the Zika virus outbreak continues to spread, women who are pregnant or planning a pregnancy should not travel to Central America and most countries in the Caribbean and South America where active infections are occurring.

In addition, pregnant women may want to reconsider summer travel plans to some areas of the United States where the Zika virus could possibly be transmitted by mosquitoes, according to Kristina Adams Waldorf, UW associate professor of obstetrics & gynecology. She has been studying infectious disease in preterm labor for 15 years.

The virus, which has no vaccine or cure, is especially dangerous for pregnant women because of its link to severe birth defects, such as microcephaly and brain tissue death.

What is Zika?

Zika is a flavivirus, a family of viruses often transmitted by ticks and mosquitos. Well-known viruses in this family include dengue fever and yellow fever.

Zika was first discovered in Uganda in the 1940s. Outbreaks previously have occurred in Africa, Southeast Asia and the Pacific Islands.

Most people infected with Zika don’t get sick. For those who do (about 20 percent), the symptoms are mild and may last 4 to 7 days. The most common symptoms of Zika are fever, rash, joint pain and conjunctivitis (red eyes).

How is it spread?

Zika is transmitted through a bite from Aedes mosquitoes. These mosquitoes are present in some parts of the United States, mostly the southern states and parts of Arizona, California and Texas. The types of mosquitoes in Washington do not carry Zika.

Recently, it was discovered that the virus can also be transmitted from a man to a woman during sex.

“We don’t think Zika can be spread by casual contact, but viral particles are present in semen, saliva, urine and breastmilk,” said Adams Waldorf. “We are unsure if it can be spread in other ways. Controlling the spread of Zika to pregnant women now is not simply a matter of mosquito control, but also of condom use to prevent sexual transmission.”

What should women do to avoid Zika infection?

No local mosquito-borne Zika virus disease cases have been reported in the United States, but there have been travel-associated cases according to the Centers of Disease Control and Prevention. Washington state has had two such cases.

“If you must travel to areas where Zika infection is a possibility, wear clothes that cover most of your skin,” said Adams Waldorf. “DEET and many other insect repellents are considered safe in pregnancy and should be used.”

If concerned, women should use condoms for several months if their partner has traveled to an area with Zika. Pregnant women should use condoms for the duration of their pregnancy.

How serious is the Zika virus for women who are trying to become pregnant or are pregnant?

The prognosis for babies born with the Zika-related microcephaly birth defect is very poor, and it’s unknown if they will reach adulthood.

“I don’t think I can overstate how worried reproductive scientists are about the current Zika epidemic for pregnant women,” said Adams Waldorf.

What is the treatment for pregnant women who get infected?

There are no therapies that can help pregnant women and babies affected by Zika, and a vaccine to prevent infection could take years. The likelihood that a woman will pass Zika to her fetus, or that the fetus will develop birth defects, is unknown.

Adams Waldorf said that the current recommendations emphasize monitoring affected pregnancies with ultrasound to look for signs of fetal brain injury. There seems to be a substantial lag time between the infection and when ultrasound abnormalities develop. And ultrasound can only detect cases of more significant fetal brain injury.

“We simply don’t know if there is also fetal brain damage from the Zika virus in cases where the ultrasound appears normal,” she said. “We also don’t know if sexual transmission of Zika virus poses a different risk of birth defects. The list of what we still don’t know about Zika and the risk of birth defects is enormous.”

If you’re concerned about Zika, travel and pregnancy talk with your healthcare provider.

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