Zika, pregnancy, and winter travel: Many unknowns, and a cautious message

Hope Ricciotti, MD
Hope Ricciotti, MD, Editor in Chief, Harvard Women's Health Watch

Follow me at @hricciot

I’ve been receiving many questions from my patients who are pregnant (or trying to get pregnant) who want to escape the Boston winter weather for warmer vacation climates, but are worried about Zika virus. Currently causing a widespread outbreak in Brazil, Zika virus is thought to be the causative agent of microcephaly in babies whose mothers were infected during pregnancy there.

I’ve been stressing that my patients should check out the CDC Zika travel notices, which warn against travel to popular winter vacation destinations in the Caribbean, Mexico, and Puerto Rico. Although there is no evidence that pre-pregnancy exposure to Zika is problematic, I have also been reinforcing to my patients that they should avoid travel to these endemic regions if they are currently pregnant or trying to get pregnant, and I’ve also been advising delaying getting pregnant for a couple of months after returning from one of these endemic areas. There have been reports that, rarely, Zika can be transmitted sexually from men to women. Therefore, men should use condoms if they have been exposed to the virus and their partner is pregnant. It is not known how long the virus may remain in semen.

When it is absolutely necessary to travel to these places while pregnant, such as for urgent family or business issues, mosquito bite prevention is key. You can avoid bites by using insect repellent, wearing appropriate attire to shield your extremities, and staying in places with windows, screen doors, or air conditioning. EPA-registered insect repellents that contain ingredients such as DEET, picaridin, and IR3535 are safe for use during pregnancy. The CDC website contains detailed information on how to avoid mosquito bites.

I’ve also received questions about vacation travel to areas such as Florida and Hawaii that are close by places with Zika transmission but not currently listed as experiencing an outbreak. So far, there has been no mosquito-borne Zika transmission in the United States, so these destinations are a good warm-climate option.

According to the CDC, only 1 in 5 people infected with Zika virus will become symptomatic. The characteristic clinical findings are a sudden fever with rash, joint aches, or conjunctivitis (reddening of the whites of the eyes), usually within 1 to 2 weeks of infection. Other reported symptoms include headache and muscle aches. The illness is usually mild, with symptoms lasting for several days to a week. The actual rates of infection with Zika virus, maternal-to-fetal transmission, immune response, exactly what the relationship is between Zika virus and fetal microcephaly, abnormal brain development, or other adverse pregnancy outcomes are not currently known.


  1. Kim Bergstrom

    Interesting. I was just in Aruba which is on the CDC list, and no matter how much I used the mosquito preventative measures, sure enough, I was the recipient of mosquito bites. I’m sure less than if I hadn’t used those measures, but bitten just the same.

    I was interested in that you recommended visiting such locations as Florida and Hawaii. If you look at the map of locations predicted for seasonal outbreak, sure enough, Florida and Hawaii are two of the locations on that map.

  2. Gene

    To whom it may concern,I’ve been following harvards study and u people are most accurate with true knowledge. What I understand there are a lot of ignorant people out there do not understand anything or even know or open up to this gland that when fully calcified is the cause of most of diseases. You people have helped solved my awareness .One more thing Obama graduated from Harvard which has correct info ,maybe he’s using the truthful studies in a reverse psychology way against us and the world.