Zika Virus Information for Cornellians

last updated 08/13/17

The U.S. Centers for Disease Control and Prevention (CDC) has issued Level 2 (Practice Enhanced Precautions) travel alerts for countries where the Zika virus is prevalent. Travelers should regularly review the travel alert updates as additional areas of concern are likely to be added to the list.

Previous alerts for areas in South Florida and Brownsville, TX have been lifted. There are no current travel alerts related to areas in the US.


Zika virus is transmitted primarily through bites of infected mosquitoes. Mosquitoes become infected when they feed on a person infected with the Zika virus and spread the illness by then biting others. The virus also is spread by infected blood (e.g. blood transfusions), and sexual and maternal-fetal transmission have been documented. Sexual transmission is more common than previously assumed.


Zika virus infection usually is present without symptoms. When symptoms are present, they last a few days to a week, are mild, and include a rash and fever, with possible conjunctivitis (red eyes), and muscle and joint pains. Symptoms requiring hospitalization are uncommon. Currently there is no vaccine to prevent or specific medicine to treat Zika.

Special concerns for women who are pregnant or at risk of pregnancy

Pregnant women and women at risk for pregnancy have special reasons for concern. Infection with Zika virus during pregnancy can cause certain birth defects, including microcephaly. The CDC's travelers health website recommends that pregnant women postpone travel to areas where Zika transmission is ongoing. Women trying to get pregnant should consult their healthcare provider before traveling to these areas and consider using a reliable method of contraception while in a Zika-risk area.

Pregnant women returning from Zika-affected areas should notify their prenatal healthcare provider of their travel history.

Sexual transmission

Zika can be passed through sex from a person who has Zika to his or her partners, even if the infected person does not have symptoms. It can be passed from a person with Zika before symptoms start, while symptoms are present, and after symptoms end. The virus may also be passed by a person who carries the virus but never develops symptoms.

Studies are underway to find out how long Zika stays in the semen and vaginal fluids of people who have Zika, and how long it can be passed to sex partners. We know that Zika can remain in semen longer than in other body fluids, including vaginal fluids, urine, and blood.  

Pregnant women should avoid the semen of male partners returning from Zika-infected areas and should contact their healthcare provider to determine how long this is necessary.

Using condoms during vaginal, anal, and oral (mouth-to-penis) sex will reduce the risk of transmission. Not having sex is the only way to be sure that someone does not get sexually transmitted Zika virus.

Travel precautions

  1. If you're traveling to one of the affected regions, especially if you're pregnant or planning to become pregnant, we encourage you to consult with a health care provider or visit our Travel Clinic prior to departure.
  2. Enter your travel in Cornell's Travel Registry.
  3. Although currently, there is no vaccine to prevent Zika, travelers can limit their exposure to Zika (and other mosquito-borne illnesses like Malaria, Dengue Fever and Chikungunya) by taking precautions to prevent mosquito bites.
    » Wear long-sleeved shirts and long pants to cover exposed skin.
    » Use EPA-registered insect repellents containing DEET, picaridin, oil of lemon eucalyptus (OLE), or IR3535.
    » Treat your clothing and gear (e.g. boots, socks, pants, hats, and tents) with permethrin or buy pre-treated items.
    » Stay and sleep in screened-in or air-conditioned rooms.
  4. Unless necessary due to a medical emergency, avoid contact with blood or blood products.
  5. Pregnant women who have two or more symptoms consistent with Zika virus disease during or within two weeks of travel, or who have ultrasound findings consistent with microcephaly, should consult with their obstetrician to be tested for Zika virus infection.
  6. If diagnosed with Zika, reduce risk of transmissions to others by taking precautions to avoid mosquito bites during the first week after your return and practicing safer sex.

Health concerns

If you have concerns about your health after returning from travel, please consult with a health care provider.
Students: please contact Cornell Health.

Testing: Cornell Health medical providers can review risk factors with students who have concerns and connect those in need with testing. (Call 607-255-5155 for an appointment.) Currently NY State makes testing available for all pregnant women and non-pregnant women and men who are symptomatic within four weeks of travel in affected countries.