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Zika Virus

Spring 2017

What is Zika Virus?

It is a virus transmitted by mosquitoes. This virus was first discovered in Uganda in 1947.

How is Zika transmitted?

It is transmitted by the bite of Aedes mosquitoes, which are usually daytime pests. Less commonly, these mosquitoes may also bite at night. There are 4 ways that Zika is transmitted.

  1. Zika mainly is spread when infected mosquitoes bite a human, who then becomes infected and acquires virus in their bloodstream. A mosquito then becomes infected by biting the infected human.
  2. Zika can be transmitted from a pregnant woman to her unborn baby in utero.
  3. Zika can be spread through sexual contact: a man/woman can transmit Zika to their sexual partners. This transmission can occur before a person has symptoms, and even if the infected source individual never develops symptoms. Zika is transmitted through semen for at least 6 months after a person has become infected.
  4. Zika virus can be spread via blood transfusion: this type of transmission has not yet been seen in the US; however, Zika endemic countries have multiple reports of blood transfusion transmission.

What countries currently have the Zika virus?

The list of countries is constantly changing. The most current list of countries can be found on the Centers for Disease Control and Prevention Zika Travel Site. In general the virus is currently in the Caribbean, Central America, Mexico, Oceania/Pacific Islands, South America, Singapore, and certain countries in Africa though accurate information is not available. Local mosquito-borne Zika virus transmission has been reported in the continental United States and also in some US territories. The CDC continues to provide up to date Zika travelers’ Information. For Zika risk-based preparedness for the United States, visit the up to date bulletins from the CDC.

Who is at risk of being infected?

Anyone traveling to one of these countries where this virus has been identified can become infected. Pregnant women are at greater risk as this virus can be transmitted to their unborn child. There is current evidence linking Zika infection during pregnancy to congenital syndromes including microcephaly. Individuals having unprotected sex (vaginal, oral, anal) within 6 months of return from a high risk area may experience the Zika disease, as well as may pass it on to their sexual partners.

What are the symptoms of Zika?

Zika disease is a mild illness and symptoms may include: fever, rash, joint pain and red eyes, which can last several days to a week. These symptoms can mirror other mosquito borne illness such as dengue, chikungunya. These symptoms begin 2-7 days after being bitten by an infected mosquito. Only 1 in 5 people infected with Zika are symptomatic. There is a rare complication called Guillain Barre Syndrome (GBS) which is a neurological condition that causes temporary paralysis or weakness. Anyone traveling to one of these countries where this virus has been identified can become infected. Pregnant women are at greater risk as this virus can be transmitted to their unborn child. There is current evidence linking Zika infection during pregnancy to congenital syndromes including microcephaly. Individuals having unprotected sex (vaginal, oral, anal) within 6 months of return from a high risk area may experience the Zika disease, as well as may pass it on to their sexual partners.

What can a traveler do to prevent exposure?

Currently the WHO and CDC recommend that pregnant women NOT travel to Zika affected areas. In addition, they advise preventive measures for all travelers to affected areas. There are no preventive vaccines or pharmaceuticals. Protect yourself and others, while living in infected areas by:

  • Wearing long sleeved shirts and long pants
  • Living in lodging with screens on the windows and doors
  • Using insect repellant that is effective: Controlled release DEET or DEET that has at least 30%. Picaridin is also an option. However, Skin-So-Soft and eucalyptus products have not been found effective.  Apply sunscreen 30 minutes before application of insect repellant, if applicable.
  • Spray your clothing with Permethrin before departing to your overseas destination
  • Sleep under mosquito nets
  • If you have been to a country where there is Zika virus (whether or not you have symptoms), it is recommended to use a condom or abstain from sex for 6 months. This includes vaginal, anal, and oral sex for at least 6 months after leaving a Zika area.
  • Men who have been to countries where there is Zika whose partner is pregnant should use condoms for the rest of the partner's pregnancy. This is especially important, even if the man does not have symptoms.
  • For people who live in countries where there is Zika, experts suggest continuing to use condoms for as long as the outbreak is happening.
  • Upon return from an endemic area, pregnancy should be avoided for at least 6 months. Infected men with pregnant partners should use condoms during intercourse and abstain from oral sex for the duration of the pregnancy.
  • Also, upon returning to continental United States from an ongoing Zika infection area, you should continue to use daily mosquito repellant for 3 weeks (dependent upon mosquito cycle).

What to do if I believe I have Zika?

If you are traveling overseas on a short term trip, you may not present with symptoms until you return to the US. If you have a fever, rash, or joint pain, come to Student Health Services. If we are closed, please visit an urgent care clinic. Please remind the medical provider that you have traveled internationally. Due to the possibility of being co-infected with other mosquito borne illnesses, acetaminophen is preferred to reduce a fever or pain.

General recommendations for travel

  • Everyone is at risk. Don’t rely on the fact that you “never get bitten” or “we never see any mosquitoes where I’m headed,” etc. Even if you are traveling to a high altitude area (over 6500 meters above sea level) where Aedes mosquitoes don’t survive, you will almost always be arriving at an airport in a lower altitude area so you will still be at risk. So unless you are coming in by helicopter to the mountaintop, you will be at risk and should take precautions.
  • Use mosquito barrier methods as noted above for all travel to Zika areas. Although Zika is endemic in most of Africa, other illnesses can be prevented such as malaria and dengue.
  • Use condoms for at least 6 months after travel or abstain from sex (oral, anal, vaginal). Avoid pregnancy for at least 6 months after travel. Currently the WHO and CDC recommend that pregnant women NOT travel to Zika affected areas.

Resources