The Zika virus outbreak continues to spread throughout the Western Hemisphere, including in wide swaths of Central and South America, 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.
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Here are the latest updates about the outbreak, which the World Health Organization has deemed a "global health emergency."
Two U.S. Service Members Diagnosed With the Zika Virus
Two male military servicemen have been diagnosed with Zika, according to Admiral Kurt Tidd, commander of U.S. Southern Command.
One military service member was deployed in Colombia and the other in Brazil, Tidd told reporters on Thursday, noting that both men have recovered from their illness and have returned to duty.
In addition, a pregnant female service member stationed in a Zika-affected country was allowed to leave her station early over concerns that she could become infected with the virus, Tidd said.
Six New Cases Reported in Florida
Florida reported on Thursday six new cases of the Zika virus in just 24 hours, bringing their total case number to 54 people diagnosed in the state.
Florida Gov. Rick Scott has already declared a state of emergency in 12 counties where the cases have been diagnosed. All of the Zika infections except one is believed to have been contracted outside the U.S. One case is believed to have been from sexual contact with a person infected with the Zika virus.
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 also been associated with a rise of microcephaly birth defect cases.
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 also 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.