'This Week' Transcript: General Martin Dempsey

October 12, 2014 — -- Below is the rush transcript of "This Week" on October 12, 2014. It may contain errors.

MARTHA RADDATZ, HOST: On ABC THIS WEEK, breaking right now -- Ebola emergency. A health care worker in Dallas tests positive for the killer virus, the first possible transmission of Ebola on U.S. soil.

How did it happen?

Are we at greater risk than we thought?

Full analysis, all the breaking details, from our Dr. Besser and on the ground in Dallas.

ISIS gaining ground -- new fears for the Iraqi capital, Baghdad.

Is the terror group about to score a major victory?

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UNIDENTIFIED MALE: We're not going to allow that to happen.

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RADDATZ: The chairman of the Joint Chiefs weighs in.

And...

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UNIDENTIFIED MALE: I've got a piece to speak.

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RADDATZ: Mr. Smith goes to Washington, the Hollywood classic turns 75. How it influenced the country and the commander-in-chief.

UNIDENTIFIED MALE: From ABC News, THIS WEEK WITH GEORGE STEPHANOPOULOS begins now.

RADDATZ: Good morning.

I'm Martha Raddatz.

And as we come on the air today, we have breaking news from Texas, the first possible transmission of Ebola in America. A health care worker who treated Ebola patient Thomas Eric Duncan has now tested positive for the virus. That word coming just hours ago. And it's raising so many questions this morning.

ABC's Tom Llamas has the very latest -- good morning, Tom.

TOM LLAMAS, ABC NEWS CORRESPONDENT: Good morning, Martha.

And we just got new information on this case.

Health officials in Texas speaking just moments ago. And what's most troubling, they say this health care worker was wearing the full protective gear while treating Mr. Duncan and still got infected.

This morning, health officials in Texas say they're very concerned.

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LLAMAS (voice-over): Overnight, dangerous developments in the fight against Ebola. A health care worker at Texas Health Presbyterian Hospital testing positive for the deadly virus.

If confirmed, this would be the first person infected inside of the US.

UNIDENTIFIED MALE: The patient's condition is stable. A close contact has also been proactively placed in isolation.

LLAMAS: Samples taken from the latest Ebola victim have now been transferred to the CDC in Atlanta for further confirmation.

The infected worker cared for Thomas Eric Duncan, the first Ebola patient diagnosed in the US. Duncan, a Liberian, started showing symptoms on September 25th, but was sent home by the hospital. It's still unclear why.

He then returned when his condition worsened. Duncan died on Wednesday, after 10 days in treatment.

Texas health officials released no information on the identity of the patient, but they say the health care worker reported a low grade fever Friday night and was then isolated.

UNIDENTIFIED MALE: That health care worker is a heroic person.

LLAMAS: In a statement, the Texas Health Department commissioner said, "We knew a second case could be a reality. We are broadening our team in Dallas and working with extreme diligence to prevent further spread."

This second possible Ebola case coming the same weekend that new airport screens for passengers flying from Ebola infected West African countries began. Enhanced screening including taking passengers' temperatures, started Saturday at JFK Airport in New York.

UNIDENTIFIED MALE: No matter how many of these procedures are put into place, we can't get the risk to zero.

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