Transcript for Ten New Cases of Zika Found in Miami Linked to Mosquitoes
And next, this evening, to an unprecedented warning now from the CDC at this hour. Telling pregnant women and their partners not to travel to a certain part of Florida. The CDC issues its first ever travel warning right here in the U.S. For a part of Miami. Ten new zika cases were found there, contracted right here in the U.S. And there is a concern that the outbreak could, in fact, spread, because the same kind of mosquito that can carry zika is now in more than half the country. ABC's Eva pilgrim tonight is on the ground in Miami, where there are new concerns. Is the pesticide now even working? Reporter: Tonight, workers are spraying in the heart of ground zero, where that zika outbreak is growing. On top of the four cases we announced on Friday, we have ten more cases. Reporter: Leading to that unprecedented travel advisory. The CDC recommending pregnant women avoid this popular area of Miami, wynwood. Impossible for her day cease Cabrera, who lives a block from the trouble zone. It's kind of scary. Reporter: The CDC telling women who visited the area, not to get pregnant for eight weeks. Health officials seen going door to door, handing out pamphlets. This man just learned he has zika. Six of those new cases here are people without symptoms, like most who get the virus. Mosquito control doing what they can to make sure she's mosquitos don't become resistant to pesticides. Mosquito control efforts don't appear to have been as effective as we had hoped. All rig Reporter: David, mosquito control is now experimenting with different types of pesticides, as they try to control this mosquito. David? Eva pilgrim with us tonight. Eva, thank you. Let's get right to ABC's Dr. Richard Besser, in Miami tonight. And rich, when you see hundreds of residents getting tested, many of these patients who had no symptoms beforehand, and now this warning not to travel to that certain neighborhood, a lot of people are going to be asking at home, how can you be sure they can con stain it to one neighborhood? Reporter: Well, I don't think that they can. This is a mosquito that's found in 30 states. We're going to see this cropping up in other places. The move the CDC is taking today, it's unprecedented. At no time in recent history have they told a group of people not to travel somewhere in America for health reasons. Unprecedented move, as you point out. And now, rich, the warning that these mosquitos could be resistant to pesticides? How much does that concern you? Reporter: Well, that's very worrisome. If you can't knock the mosquito down, you have to rely on people using repellent, getting rid of free-standing water to control this disease. It's much harder. All right, rich, thank you. And Dr. Besser will stay on
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