Zika virus: First infection transmitted through sex reported in US

US health officials have reported the first known case of the Zika virus transmitted by sex in Texas. The Centers for Disease Control and Prevention confirmed a patient had been infected in Dallas County. The patient reportedly became infected after having sexual contact with an individual who had returned from Venezuela, where Zika virus is present.

According to the BBC, there is no known evidence that the disease has been passed on by mosquitoes in the US and this would be the first known infection in mainland US.

"Now that we know Zika virus can be transmitted through sex, this increases our awareness campaign in educating the public about protecting themselves and others," Zachary Thompson, director of Dallas County Health and Human Services, said in a press release. "Next to abstinence, condoms are the best prevention method against any sexually-transmitted infections," Thompson added.

The Texas Department of State Health Services said in its statement: "Case details are being evaluated, but the possibility of sexual transmission from an infected person to a non-infected person is likely in this case."

The reported infection case comes a day after the World Health Organization (WHO) declared Zika virus to be a global public health emergency. According to Reuters, the virus has been linked to severe birth defects – including microcephaly – in thousands of babies, particularly in Brazil. It was originally believed to be spread through mosquito bites of the Aedes genus, so transmission through sexual conduct could represent a troubling development.