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Zika Virus: Answers from Maternal-Fetal Medicine Specialist Jeanne Sheffield
As the Zika virus becomes more prominent throughout the Americas, awareness and prevention efforts are increasing for expectant mothers.
Jeanne Sheffield, M.D., director of the Division of Maternal-Fetal Medicine at Johns Hopkins, is an internationally recognized expert in pregnancy and infectious disease. After Zika virus outbreaks began in 2015, she worked with the Centers for Disease Control and Prevention, the American College of Obstetricians and Gynecologists, and the Society for Maternal-Fetal Medicine to publish guidance for health care providers. Here’s what you need to know about the Zika virus:
Q: What is the Zika virus?
Most people who contract Zika don’t experience any symptoms. For those who do, the effects of the illness are usually very mild — fever, muscle aches and rash are the most common symptoms — and it’s rare to see people develop issues that require them to go to the hospital.
Q: How do you contract the Zika virus?
A: Most people get the Zika virus from a mosquito bite. Sexual transmission is possible, through both vaginal and anal sex. Expectant mothers infected with Zika virus can pass it onto the fetus through the umbilical cord or at the time of delivery.
Q: Why have pregnant women been particularly affected by the Zika virus?
A: Being pregnant does not necessarily make you more vulnerable to contracting the virus, but if you are infected with Zika and pass it on to your baby, there is a greater risk of birth defects. We’ve known about Zika for decades, but it wasn’t until the large Brazilian outbreak in 2015 that the link between the virus and fetal microcephaly, as well as many other abnormalities, was discovered, and we realized the significant impact of Zika.
Q: If Zika has been around for decades, why is it only now becoming a concern?
A: There are a few possibilities why the Zika virus is now becoming a concern:
- Zika may have mutated and become more virulent.
- Once it reached the Americas, it may have been able to be transmitted more frequently.
- It may have been underreported previously.
We aren’t entirely sure at this time, but as we continue to perform research and promote awareness, there will be a higher likelihood that more cases will be reported and further discoveries can be made.
Q: The Centers for Disease Control and Prevention has advised pregnant women to postpone travel to more than 20 countries in South and Central America and the Caribbean. Why are these countries at greater risk for Zika outbreaks?
A: The countries on the Centers for Disease Control and Prevention (CDC) list have all experienced Zika outbreaks so far. This is likely due to the warmer climates present in these countries, which are ideal for Zika-transmitting mosquitos. These mosquitos, primarily of the Aedes species, are sometimes found in the southern United States as well, making it imperative to promote awareness of Zika virus in the U.S.
Q: What treatments are currently available for Zika?
A: While antiviral treatment is being investigated, nothing is currently available. Right now, only symptomatic relief is possible for illness-related fever or rash. The most important thing for women is preventive measures.
In addition to the CDC’s travel advisory, the governments of several affected countries are telling women to delay childbearing for a few years. These are significant steps that underline the seriousness of this issue and the necessity for precaution.
Overall, the best form of prevention is to limit your exposure by not traveling to affected countries. But if you are pregnant or considering pregnancy and have to travel to affected areas, you can do the following:
- Wear protective gear, like long-sleeve shirts and pants. Avoid skin exposure as much as possible to prevent mosquito bites.
- Use Environmental Protection Agency-approved insect repellents as directed, which are safe for pregnant women.
- If you are pregnant and have a male partner who travels to an area of active Zika virus infection, you should abstain from sexual activity or consistently and correctly use condoms during sex for the duration of the pregnancy.
- Talk to your Gyn/Ob if you have traveled to an affected area. Your physician will perform a blood test for evidence of Zika virus infection. You will also have at least one ultrasound to evaluate your fetus for infection.