8 more countries added to Zika virus travel alerts

What You Need to Know About the Zika Virus

The Centers for Disease Control (CDC) on Friday added eight countries to its travel advisories for Zika virus.

The advisories, which recommend that all travelers avoid mosquitoes and that pregnant travelers consider postponing, now include Barbados, Bolivia, Ecuador, Guadeloupe, Saint Martin, Guyana, Cape Verde and Samoa.

SEE ALSO: What Zika virus means for your travel plans

The CDC had already issued travel advisories for Colombia, El Salvador, French Guiana, Guatemala, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Suriname, Venezuela and the Commonwealth of Puerto Rico.

While only one in five people infected by Zika virus show symptoms, and those symptoms are typically mild, there is increasing concern that the disease can cause microcephaly — a condition which causes underdeveloped brains in newborns. For that reason, the CDC as well as several foreign authorities have warned of the risks to pregnant women.

See the extreme measures being taken in an attempt to control the Zika virus:

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Zika, health agents trying to eradicate Zika mosquitoes in South America, Central America
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8 more countries added to Zika virus travel alerts
RECIFE, BRAZIL - FEBRUARY 01: David Henrique Ferreira, 5 months, who was born with microcephaly, is examined by a doctor on February 1, 2016 in Recife, Pernambuco state, Brazil. Ferreira's mother says she spends up to eight hours per day in transit on buses, three days per week, to visit a litany of doctors with David. In the last four months, authorities have recorded thousands of cases in Brazil in which the mosquito-borne Zika virus may have led to microcephaly in infants. The ailment results in an abnormally small head in newborns and is associated with various disorders including decreased brain development. The World Health Organization (WHO) declared the Zika virus a 'public health emergency of international concern' today. (Photo by Mario Tama/Getty Images)
Health ministry personnel fumigate a classroom against the Aedes aegypti mosquito, vector of the dengue, Chikungunya and Zika viruses in Tegucigalpa, , on February 1, 2016. Honduran President Juan Orlando Hernandez on Friday declared the country on a preventive state of alert due to the Zika virus which in the last 44 days killed a person and infected some 1000. AFP PHOTO/Orlando SIERRA. / AFP / ORLANDO SIERRA (Photo credit should read ORLANDO SIERRA/AFP/Getty Images)
Members of the Migente foundation check mosquito traps in the Paris neighborhood, Bello municipality, Antioquia department, Colombia on January 26, 2016. The Study and Control of Tropical Diseases Program (PECET) of Antioquia's University released one year ago Aedes aegypti mosquitos carrying the Wolbachia pipientis bacteria, which prevents them from transmitting the Zika and dengue viruses, as part of project to fight dengue. The Zika virus, a mosquito-borne disease suspected of causing serious birth defects, is expected to spread to all countries in the Americas except Canada and Chile, the World Health Organization said. AFP PHOTO /Raul ARBOLEDA / AFP / -- / RAUL ARBOLEDA (Photo credit should read RAUL ARBOLEDA/AFP/Getty Images)
A photographer walks through the fumes as Health Ministry employee fumigate against the Aedes aegypti mosquito to prevent the spread of the Zika virus in Soyapango, six km east of San Salvador, on January 21, 2016. Health authorities have issued a national alert against the Aedes Aegypti mosquito, because of the link between the Zika virus and microcephaly and Guillain-Barré Syndrome in fetuses. AFP PHOTO/Marvin RECINOS / AFP / Marvin RECINOS (Photo credit should read MARVIN RECINOS/AFP/Getty Images)
Army soldiers check for Aedes aegypti mosquito larvae during a clean-up operation against the insect, which transmits the Zika virus, in Sao Paulo, Brazil on January 22, 2016. AFP PHOTO/Miguel SCHINCARIOL / AFP / Miguel Schincariol (Photo credit should read MIGUEL SCHINCARIOL/AFP/Getty Images)
Army soldiers check for Aedes aegypti mosquito larvae during a clean-up operation against the insect, which transmits the Zika virus, in Sao Paulo, Brazil on January 22, 2016. AFP PHOTO/Miguel SCHINCARIOL / AFP / Miguel Schincariol (Photo credit should read MIGUEL SCHINCARIOL/AFP/Getty Images)
Army soldiers check for Aedes aegypti mosquito larvae during a clean-up operation against the insect, which transmits the Zika virus, in Sao Paulo, Brazil on January 22, 2016. AFP PHOTO/Miguel SCHINCARIOL / AFP / Miguel Schincariol (Photo credit should read MIGUEL SCHINCARIOL/AFP/Getty Images)
A health agent from the Sao Paulo secretariat of public health and army soldiers check for Aedes aegypti mosquito larvae during a clean-up operation against the insect, which transmits the Zika virus, in Sao Paulo, Brazil on January 22, 2016. AFP PHOTO/Miguel SCHINCARIOL / AFP / Miguel Schincariol (Photo credit should read MIGUEL SCHINCARIOL/AFP/Getty Images)
A Health Ministry employee fumigates a home against the Aedes aegypti mosquito to prevent the spread of the Zika virus in Soyapango, six km east of San Salvador, on January 21, 2016. Health authorities have issued a national alert against the Aedes Aegypti mosquito, because of the link between the Zika virus and microcephaly and Guillain-Barré Syndrome in fetuses. AFP PHOTO/Marvin RECINOS / AFP / Marvin RECINOS (Photo credit should read MARVIN RECINOS/AFP/Getty Images)
A Health Ministry employee fumigates a home against the Aedes aegypti mosquito to prevent the spread of the Zika virus in Soyapango, six km east of San Salvador, on January 21, 2016. Health authorities have issued a national alert against the Aedes Aegypti mosquito, because of the link between the Zika virus and microcephaly and Guillain-Barré Syndrome in fetuses. AFP PHOTO/Marvin RECINOS / AFP / Marvin RECINOS (Photo credit should read MARVIN RECINOS/AFP/Getty Images)
TOPSHOT - A Health Ministry employee fumigates a home against the Aedes aegypti mosquito to prevent the spread of the Zika virus in Soyapango, six km east of San Salvador, on January 21, 2016. Health authorities have issued a national alert against the Aedes Aegypti mosquito, because of the link between the Zika virus and microcephaly and Guillain-Barré Syndrome in fetuses. AFP PHOTO/Marvin RECINOS / AFP / Marvin RECINOS (Photo credit should read MARVIN RECINOS/AFP/Getty Images)
Health ministry employees spray to eliminate breeding sites of the Aedes Aegypti mosquito, which transmits diseases such as the dengue, chicunguna and Zica viruses, in a Tegucigalpa cemetery on January 21, 2016. The medical school at the National Autonomous University of Honduras (UNAH) recommended that women in the country avoid getting pregnant for the time being due to the presence of the Zika virus. If a pregnant woman is infected by the virus, the baby could be born with microcephaly. AFP PHOTO/Orlando SIERRA / AFP / ORLANDO SIERRA (Photo credit should read ORLANDO SIERRA/AFP/Getty Images)
A specialist fumigates the Nueva Esperanza graveyard in the outskirts of Lima on January 15, 2016. Health officials fumigated the largest cementery in Peru and second largest in the world to prevent Chikunguya and Zika virus, which affect several South American countries. AFP PHOTO/ERNESTO BENAVIDES / AFP / ERNESTO BENAVIDES (Photo credit should read ERNESTO BENAVIDES/AFP/Getty Images)
View of the Nueva Esperanza graveyard as it is fumigated in the outskirts of Lima on January 15, 2016. Health officials fumigated the largest cemetery in Peru and second largest in the world to prevent Chikunguya and Zika virus, which affect several South American countries. AFP PHOTO/ERNESTO BENAVIDES / AFP / ERNESTO BENAVIDES (Photo credit should read ERNESTO BENAVIDES/AFP/Getty Images)
A pregnant woman is attended at the Maternal and Children's Hospital in Tegucigalpa on January 21, 2016. The medical school at the National Autonomous University of Honduras (UNAH) recommended that women in the country avoid getting pregnant for the time being due to the presence of the Zika virus. If a pregnant woman is infected by the virus, the baby could be born with microcephaly. AFP PHOTO/Orlando SIERRA / AFP / ORLANDO SIERRA (Photo credit should read ORLANDO SIERRA/AFP/Getty Images)
A pregnant woman waits to be attended at the Maternal and Children's Hospital in Tegucigalpa on January 21, 2016. The medical school at the National Autonomous University of Honduras (UNAH) recommended that women in the country avoid getting pregnant for the time being due to the presence of the Zika virus. If a pregnant woman is infected by the virus, the baby could be born with microcephaly. AFP PHOTO/Orlando SIERRA / AFP / ORLANDO SIERRA (Photo credit should read ORLANDO SIERRA/AFP/Getty Images)
Aedes aegypti mosquitos are seen in containers at a lab of the Institute of Biomedical Sciences of the Sao Paulo University, on January 8, 2016 in Sao Paulo, Brazil. Researchers at the Pasteur Institute in Dakar, Senegal are in Brazil to train local researchers to combat the Zika virus epidemic. / AFP / NELSON ALMEIDA (Photo credit should read NELSON ALMEIDA/AFP/Getty Images)
Aedes aegypti mosquitos are seen in containers at a lab of the Institute of Biomedical Sciences of the Sao Paulo University, on January 8, 2016 in Sao Paulo, Brazil. Researchers at the Pasteur Institute in Dakar, Senegal are in Brazil to train local researchers to combat the Zika virus epidemic. / AFP / NELSON ALMEIDA (Photo credit should read NELSON ALMEIDA/AFP/Getty Images)
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The travel advisories could spell terrible news for the tourism economies of these countries, in particular Brazil, which is hoping for a surge in tourism for the 2016 Olympics to help with a deep recession.

The New York Times also reported Friday the virus could be the cause of a rare syndrome surging in Brazil, which leaves patients almost "completely paralyzed" for weeks.

The CDC reports Guillain-Barré syndrome has been seen in patients with probable Zika virus infections in both Brazil and French Polynesia. Research is underway to determine if there is a link. It is not clear from the CDC's guidance if there is potential danger only for pregnant women or also women who may become pregnant in the future. It's also unclear whether the risk for pregnant women is higher in certain trimesters. The agency recommends women who are trying to become pregnant speak with their doctor before traveling to the included countries.

The CDC recommendations for women who are pregnant or trying to become pregnant are:

  • Pregnant women in any trimester should consider postponing travel to the areas where Zika virus transmission is ongoing. Pregnant women who must travel to one of these areas should talk to their doctor or other healthcare professional first and strictly follow steps to avoid mosquito bites during the trip.

  • Women trying to become pregnant should consult with their healthcare professional before traveling to these areas and strictly follow steps to prevent mosquito bites during the trip.

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