First known case of female-to-male Zika transmission announced

(CNN)In another startling Zika development, the first case of female-to-male sexual transmission of the Zika virus has occurred in New York City, the Centers for Disease Control and Prevention announced Friday. Up until now, it was thought that the only likely route of sexual transmission was male-to-female or male-to-male.

The surprising development prompted the CDC to immediately change its guidance for pregnant women in relation to the virus. Even though no cases of woman-to-woman Zika transmission have yet been reported, the CDC now urges female sexual partners of pregnant women to use barrier methods every time they have sex if they live in or have recently returned from an area with active Zika transmission.
    Studies have already shown that Zika remains in both urine and saliva long after it resolves in the blood, even though the likelihood of transmission via that route is considered extremely low.

    Slow rise of cases?

    According to the latest CDC statistics, there are only 14 known cases of sexually transmitted Zika in the United States. To put that into comparison, there have been 1,305 travel-related cases of Zika in the mainland United States and no known cases where Zika has been transmitted via a mosquito bite. But it's also true that four out of five people who come down with Zika have no symptoms, so experts admit that the numbers could be much higher.

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    And in Puerto Rico, where Zika is spreading rapidly, officials can't monitor sexual transmission because "it is not possible to determine whether infection occurred due to mosquito-borne or sexual transmission," the CDC said.

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