Zika Virus - CDC's Travel Warnings and What You Should Know to Prevent Infection

Susanna Sisson's picture

The CDC has recently issued travel warnings (level two out of three), especially for pregnant women going to Mexico, Central America, South America, and the Caribbean, due to the outbreak of Zika virus in these regions. [5] The Zika Virus, a type of mosquito-borne flavivirus similar to Dengue fever is associated with birth defects. The alert includes women who are pregnant in any trimester and women who are considering becoming pregnant. [3]


According to the CDC, only 1 in 5 people infected with the disease become symptomatic, with rare hospitalizations and no known deaths. Symptoms are usually mild and include fever, rash, joint pain, or conjunctivitis (red eyes), muscle pain and headache. [2]

The danger of contracting the virus is to a developing fetus. Infection can result in the underdevelopment of the baby’s brain and cranium which may also include a sloping forehead. The condition, known as microcephaly is irreversible. Although there is no treatment for microcephaly, babies born with mild microcephaly may have improved quality of life through speech and occupational therapy. Those born with severe cases either need lifelong care or die.

The Zika virus is usually transmitted by the Aedes aegypti mosquito -- a common culprit in infecting humans with viruses and which can carry Denge and Yellow fever which is typically found in subtropical climates. The virus is spread if a mosquito bites someone infected with the disease and transmits the virus to another person. People infected with the virus are not contagious however the CDC recommends that anyone with a known infection avoid mosquito bites because during the first week of infection, Zika virus can be found in the blood and passed from an infected person to another mosquito through mosquito bites, thus causing the spread of the disease.

Zika virus is not new, having been discovered in 1947 in the Zika Forest in Uganda. The virus was isolated from a human in Nigeria in 1954. Zika was known only in a narrow equatorial belt in Africa and Asia until 2007 when a case was diagnosed in the Federation of Micronesia, a chain of thousands of islands in the western Pacific Ocean.

Until recently, the Zika virus was not associated with the congenital brain condition, but scientists have linked the condition to the virus due to an increase in cases of microcephaly in Brazil from 147 in 2014 to 3,500 in 2015 resulting in the death of 46 babies who were severely affected. Testing of two babies who died after birth and two who died in utero revealed they were infected with the virus. Brazil saw its first case of Zika in May, 2014. In 2015, Brazil saw more than 1 million cases of Zika and then a few months later there were over 3,000 babies born with microcephaly, about ten times the number of cases usually seen in the country each year. There's also a possibility that Zika causes Guillain-Barré syndrome and it has been linked to seven deaths. Because of the sharp increase in cases of microcephaly, especially in the northern part of the country, Brazil has declared a state of emergency and recommends women delay getting pregnant.

The CDC has confirmed just one case of an infection that occurred on U.S. territory, Puerto Rico in December, 2015. The case suggested local transmission since the patient had not been traveling. [12]

There have been at least 22 cases of Zika recorded in the United States although those were cases in which the disease was acquired abroad and returned with the virus. Fourteen cases were recorded between 2007 and 2014.


Another eight cases of U.S. travelers who became ill were confirmed by the CDC in 2015 and 2016, a number the CDC warns may rise.

Recently a baby born on the island of Oahu, Hawaii, with microcephaly tested positive for Zika virus. It is believes the mother contracted the virus when she was living in Brazil in May of 2015. Six people have tested positive for the virus in Hawaii, although US health officials state that these people are not infectious. [9][10]

Other cases in the U.S. have been popping up including one in Houston, Texas. The patient had recently traveled to Latin America. [7]

Three confirmed cases have been reported in Florida, two in Miami Dade County connected to people who went to Colombia and one in Hillsborough County. That patient had traveled to Venezuela. [8]

“What we need to do,” says Dr. Peter Hotez of Baylor College of Medicine “is the actively conduct studies in the region to determine if the mosquitoes have the virus.” The mosquito which typically carries the Zika virus is found primarily in the Southern Coastal states as far south at Florida and as far north as South Carolina. [4]

While there have been no cases of Zika virus in the U.S. the CDC warns to take precautions;
• Remove standing water
• Chlorinate swimming pools
• Maintain window and door screens
• Cover open skin
• Use insect repellent
• Avoid travel to countries with known outbreaks

The CDC has send two teams to Brazil to study the virus. The travel advisory may have serious economic repercussions as Brazil will host the 2016 Summer Olympics.

1. http://www.cdc.gov/zika/
2. http://www.cdc.gov/zika/symptoms/index.html
3. http://wwwnc.cdc.gov/travel/notices/alert/zika-virus-caribbean
4. http://www.nbcnews.com/health/health-news/zika-virus-five-things-you-need-know-n496766
5. http://www.cbsnews.com/news/cdc-travel-warning-issued-for-pregnant-women-amid-zika-outbreak/
6. http://www.cbsnews.com/news/zika-virus-what-you-need-to-know/
7. http://www.houstonpress.com/news/harris-county-has-its-first-case-of-the-zika-virus-8063850
8. http://www.wtsp.com/story/news/health/2016/01/19/case-zika-virus-confirmed-hillsborough/79002258/
9. http://www.cnn.com/2016/01/17/health/hawaii-zika-baby-microcephaly/
10. https://www.rt.com/news/329405-zika-virus-baby-hawaii/
11. http://www.cnn.com/2016/01/17/health/hawaii-zika-baby-microcephaly/
12. http://www.vox.com/2016/1/5/10716530/zika-virus-disease