The U.S. Centers for Disease Control and Prevention is investigating at least 14 reported cases of sexually transmitted Zika virus, according to a new health alert from the agency.
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The high number of cases led the CDC to issue the health alert as a "strong reminder" to the public and medical providers that the Zika virus can be transmitted through sexual contact and people should take precautions if they have been to an area with ongoing Zika virus transmissions. The new reported cases "suggest sexual transmission may be a more likely means of transmission for Zika virus than previously considered," the CDC said.
Of the 14 reported cases of sexually transmitted Zika virus, "several" involved pregnant women, according to the CDC.
The Zika virus primarily is spread to humans through mosquitoes but in rare cases has been transmitted through sexual contact and blood transfusions. More than 100 people in the U.S. have been diagnosed with the Zika virus in the U.S., according to state health departments. None of the cases are believed to have been acquired from mosquitoes spreading the disease in the U.S.
The Zika virus often causes mild symptoms, including fever, fatigue and rash that clear up in approximately a week. However, the virus has also been associated with a rise of the birth defect microcephaly in Brazil. The birth defect is characterized by an abnormally small head and brain that may lead to significant developmental delays.
Prior to these 14 reported cases, a case of sexually transmitted Zika virus was reported in Dallas, Texas, prompting health officials to issue guidelines to stop Zika transmission through sexual contact.
They have currently advised men who travel to an area with active Zika transmission and who have a pregnant partner to abstain from sexual activity or use barrier contraception for the duration of the pregnancy.
They also advise men concerned about the Zika virus to consider using condoms or abstaining from sex, even if their partners are not pregnant.