Zika Virus Outbreak Updates: WHO Says Vaccine Trials Are 'Months' Away

— -- The Zika virus outbreak continues to spread throughout the Western Hemisphere and concerns are growing for pregnant women because the mosquito-borne virus has been linked with a serious birth defect called microcephaly, characterized by an abnormally small head and brain in infants.

Here are the latest updates about the outbreak, which the World Health Organization has deemed a "global health emergency."

WHO Says Vaccine Trials Are 'Months' Away

The World Health Organization said that vaccine trials to combat the Zika virus could be more than a year away, according to the Associated Press.

Marie-Paule Kieny, WHO assistant director-general for health systems and innovation, told reporters today that there are 15 companies or groups that may participate in vaccine development. However, large-scale trials will still take at least 18 months, she said.

Department of Homeland Security Releases Zika Plan

The Department of Homeland Security released an outline of its plan to deal with the ongoing Zika outbreak. The agency said it is closely coordinating with the U.S. Centers for Disease Control and Prevention (CDC) and the Department of Health and Human Services to combat the virus.

The plan includes continued monitoring of infected travelers at the border, enhanced precautions at detention facilities and educating department employees to recognize signs and symptoms of the virus.

No Countries Have Pulled Out of Olympics Over Zika Says IOC President

Thomas Bach, the president of the International Olympic Committee, told reporters that countries participating in the Olympics had "no intention" of skipping the games, according to the Associated Press.

Bach, speaking before the Winter Youth Olympics, said he had confidence in the Brazilian authorities to stop the viral outbreak.

"This does not exclude that we are taking the situation very seriously," he said.

What Does the Virus Do?

Common symptoms of the Zika virus include fever, rash, joint pain and conjunctivitis, according to the CDC. Approximately one in five people infected with the virus show symptoms. Severe complications from the virus that require hospitalization are rare, according to the CDC.

The virus has been associated with the birth defect microcephaly.

The CDC is also investigating if a rare paralysis syndrome called Guillain-Barre is related to the virus. The syndrome is an immunological reaction that can occur after other viral or bacterial infections.

How Is It Transmitted?

The virus is transmitted mainly through the bite of the Aedes aegypti species of mosquito. This is the same type of mosquito that spreads dengue fever. The Aedes albopictus species has also been identified as a potential carrier.

Before the current outbreak, the virus had been found mainly in tropical settings in Africa, Southeast Asia and the Pacific Islands. An outbreak of the disease in Brazil led to an alert by the Pan American Health Organization last May.

Health officials have also reported rare cases of transmission through blood transfusions and through sexual contact, including one case in Dallas, Texas.

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