Zika Virus Outbreak Updates: FDA Issues New Guidelines on Blood Donation

— -- 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."

New FDA Recommendations on Blood Donation

The U.S. Food and Drug Administration issued recommendations today to safeguard the donated blood supply during the Zika virus outbreak. The agency is recommending that those at risk of having been infected with the Zika virus should not donate blood for four weeks. These include those who have had Zika virus symptoms or sexual contact with people who have traveled to countries known to have ongoing transmissions.

“The FDA has critical responsibilities in outbreak situations and has been working rapidly to take important steps to respond to the emerging Zika virus outbreak,” Dr. Luciana Borio, the FDA’s acting chief scientist, said in a statement today. “We are issuing this guidance for immediate implementation in order to better protect the U.S. blood supply.”

Additionally, the FDA recommends that no blood be used from areas where there is active transmission of the virus. No transmissions of the virus between mosquito and human have been reported in the U.S.

WHO Looks at GMO Mosquitoes

In a new report, officials from the World Health Organization said they are looking into new forms of mosquito control, including "a genetically modified prototype mosquito."

The WHO Vector Control Advisory Group is evaluating new tools in an effort to kill the insects that spread the Zika virus. In addition to GMO mosquitoes, the group is also looking at sterilizing a male mosquitoes using a low dose of radiation. Additionally, a bacteria called "Wolbachia" could be used to stop mosquito eggs from hatching. The bacteria is not infectious to humans or other mammals.

"Given the magnitude of the Zika crisis, WHO encourages affected countries and their partners to boost the use of both old and new approaches to mosquito control as the most immediate line of defence," WHO officials said in the report today.

What Does the Virus Do?

Common symptoms of the Zika virus include fever, rash, joint pain and conjunctivitis, according to the U.S. Centers for Disease Control and Prevention. 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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