We hope this guide will help inform you about the Zika virus. It is a synopsis of information currently available, relating to a topic that is currently evolving.
What is Zika?
Zika is a viral disease primarily spread through the bite of an infected Aedes species mosquito. It was first discovered in 1947 and is named after the Zika Forest in Uganda. The first human cases of Zika were detected in 1952. In May 2015, the Pan American Health Organization (PAHO) alerted the first confirmed Zika virus infection in Brazil. In February 2016, the World Health Organization (WHO) declared Zika virus a Public Health Emergency of International Concern (PHEIC).
How is Zika Transmitted?
- Through mosquito bites. This is the most common way that the disease is spread. The Aedes species mosquito is the same that spread dengue and chikungunya viruses. The mosquito becomes infected when they feed from a person already infected with the virus and then spread it to other people through bites.
- Through sexual contact. The virus is present in bodily fluids, including semen. The virus is present longer in semen than in blood. It can be spread from a man to his sexual partner through unprotected intercourse. There have been no reports of transmission from a woman through intercourse.
- Through blood transfusion. There have been reports of transmission via blood transfusion in Brazil, but none confirmed in the United States.
- From mother to baby. A pregnant woman can pass Zika to her fetus during pregnancy or around the time of delivery. There are no reports of infants getting Zika through breastfeeding.
Areas with Zika
Areas with active mosquito-borne transmission of Zika include Africa, Southeast Asia, the Pacific Islands and the Americas, including Brazil, Puerto Rico and the U.S. Virgin Islands. The latest travel information from the CDC can be found here. No local mosquito-borne Zika cases have been reported in the U.S. Only travel-associated cases have been reported in the U.S. Areas with these cases can be found here.
What are the Symptoms Associated with Zika?
Most people infected with Zika (about 80%) will not experience any symptoms. Those who do have symptoms usually have a mild illness. The symptoms typically start 2 to 7 days after being bitten by an infected mosquito. The symptoms may last several days to a week. The most common symptoms are fever, rash, joint or muscle pain, headache and pink eye (conjunctivitis). People rarely get sick enough to go to the hospital and very rarely die of Zika. Zika virus remains in the blood for about a week, possibly longer in some people. It remains in semen for at least 2 weeks and possibly up to 10 weeks. Once a person has been infected, he or she is likely immune from future infections.
How is Zika Diagnosed?
Zika can be diagnosed by testing blood or urine. The urine samples should be collected less than 14 days after the onset of symptoms. If you have signs or symptoms of Zika, see your health care provider right away to be tested. The CDC does not recommend Zika testing for all pregnant women, but if you may have been exposed or you have symptoms, see your health care provider.
How is Zika Treated?
There is no medicine to treat Zika virus, and there is no vaccine to prevent it. If you have symptoms, it is recommended to:
- Stay well hydrated; drink plenty of fluids.
- Get lots of rest.
- Take acetaminophen (Tylenol) to help with fever and pain.
- Do not take non-steroidal anti-inflammatory drugs (NSAIDs) until dengue can be ruled out.
How is Zika Prevented?
There is no vaccine to help prevent Zika. If you are pregnant or trying to get pregnant, here are ways to reduce your risk of getting Zika:
- Do not travel to a Zika-affected area unless it cannot be avoided. If you do plan travel to these areas, consult with your health care provider first.
Prevent mosquito bites:
- Wear long-sleeved shirts, long pants, hats, shoes and socks.
- Stay in places with air conditioning and window screens to help keep mosquitos outside.
- Use a mosquito bed net if necessary (overseas or outside).
- Use Environmental Protection Agency (EPA)-registered insect repellents with one of the following active ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus (not for children under 3 years old) or para-menthane-diol.
- These are safe, even for pregnant and breastfeeding women.
- Follow the instructions on the product label.
- Apply sunscreen first and then the insect repellent.
- Treat gear and clothing with permethrin (do not use permethrin directly on your skin).
- Remove still water from inside and outside your surroundings. This is where mosquitoes can lay eggs.
Zika and Pregnancy
Pregnant women can be infected with Zika and can pass the virus to a fetus during pregnancy or at delivery. It is not known how the virus will affect her or the pregnancy, how likely it is to be passed to the fetus and what harm the infection may cause. The following have been linked to Zika in pregnancy:
- Microcephaly: this is when a baby’s head is smaller than expected and the baby’s brain is smaller and doesn’t develop as expected.
- Other causes of microcephaly: changes in the babies’ genes, certain infections during pregnancy, toxin exposure during pregnancy.
- Other birth defects including hearing loss, eye defects and impaired growth.
It is believed that a Zika virus infection in a woman who is not pregnant should not create problems in a future pregnancy after the virus has cleared from her blood.
Women Who Desire Pregnancy
Women who are diagnosed with Zika should wait at least 8 weeks from the time symptoms start prior to attempting pregnancy. Men who are diagnosed with Zika should wait at least 6 months from symptom onset prior to attempting pregnancy. Women and men with possible Zika exposure but no symptoms should wait at least 8 weeks after the last date of exposure before attempting to get pregnant. There is no evidence that Zika will cause problems with a fetus after an infection has resolved.