ATLANTA, Ga. (WPVI) --The CDC has posted a new map, showing where the Aedes aegypti mosquito and its cousin, the Asian tiger mosquito, can live.
Instead of just in the South and Southwest, as experts have previously said, the range may stretch up and into the Delaware Valley area as well.
This doesn't mean they are here now.
And there have been no reports of Zika-infected mosquitoes on the U.S. mainland.
But the CDC does want everyone to take precautions to prevent mosquito bites and to control mosquitoes.
To spread Zika, a mosquito has to bite someone infected, and then bite someone else.
Unlike other areas where Zika is spreading, the U.S. has more window screens and air conditioning.
That will help keep mosquitoes out of homes, which is where Aedes mosquitoes like to hide.
The aggressive Asian tiger mosquitoes are already in the Pennsylvania, New Jersey and Delaware areas.
They are known to spread West Nile virus, and health officials say, theoretically, they could spread the Zika virus.