The Center for Disease Control and Prevention (CDC) says there are now over 300 pregnant woman in the US with "laboratory evidence of possible Zika virus infection". Not every baby that’s born with Zika will have microcephaly or brain defects, but the CDC estimates the number between 1-13 percent.
The CDC has also advised pregnant woman to avoid travelling to the areas where mosquitos have been shown to carry Zika. This has also put a strain on the Olympic Games in Rio de Janeiro, with some athletes speaking out about those competing this summer.
As reported on MSNBC this morning, all known cases of the Zika virus currently identified in the U.S. have been contracted outside of the country. The concern, of course, is that one or more of the several hundred people known to have it could be bitten by a mosquito in the U.S. and that could then accelerate the spread.