Zika virus infection reported in US

The first known case of the Zika virus being sexually transmitted in the US has been reported in Texas.

The Centers for Disease Control and Prevention confirmed a patient was infected in Dallas County, health officials in Texas said.

A patient was apparently infected after having sexual contact with someone who returned from a country where the disease is present.

There is not yet evidence of Zika being passed on by mosquitoes in the US.

This would be the first known infection to take place in the mainland US.

The World Health Organization has declared the Zika virus a global public health emergency.

The infection may be linked to thousands of babies being born with underdeveloped brains.

"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," said Zachary Thompson, director of Dallas County Health and Human Services, in a news release.

"Next to abstinence, condoms are the best prevention method against any sexually-transmitted infections."