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To Protect US From Ebola, Stop It at Its Source: CDC Director
PHOTO: An Ebola virus is shown in this undated file image by the CDC.

The Centers for Disease Control and Prevention is escalating its response to the deadly Ebola outbreak, sending 50 staff members to West Africa to stop the disease at the source, CDC Director Dr. Tom Frieden said today.

"We are surging our response," Frieden told ABC News' George Stephanopoulos. "We're going to put 50 staff on the ground in these three countries to help stop the outbreak in the next 30 days."

Meanwhile, Dr. Kent Brantly, who contracted the disease in Liberia where he was volunteering to fight the outbreak, arrived Saturday at Emory University Hospital in Atlanta, becoming the first Ebola patient in the United States. A second American Ebola patient, aid worker Nancy Writebol, is expected to arrive in the U.S. in the coming days.

Five Simple Questions About Ebola Answered

Frieden dismissed a tweet by Donald Trump demanding the United States "stop all flights from Ebola infected countries."

"We're not going to hermetically seal the borders of the U.S.," he said. "We're reliant and interdependent with the world for travel, for trade, for economy, for our families and communities."

Instead, Frieden said, "The single most important thing we can do to protect Americans is to stop this disease at the source in Africa."

What You Need To Know About the Ebola Outbreak

Live Blog: Ebola Outbreak

The latest Ebola outbreak is the deadliest in history, with more than 700 people having died from the disease so far. The virus is spread through bodily fluids and the current outbreak is centralized in three African countries -- Liberia, Guinea, and Sierra Leone.

There is no known cure or vaccine for Ebola, but there has been promising research towards the development of both post-exposure treatment and a vaccine. Until that research pays off, health officials say there are important steps that can help control the spread of the life-threatening disease.

"What we can do and what we're doing is surging our response to put out the embers, because Ebola is really like a forest fire," Frieden said this morning. "If you leave one ember burning, it can flare up again. That's why it's so important that we control it."

Ebola Patients Coming to the US: How Safe Are We?

The difficulty in containing this outbreak, ABC News chief health and medical editor Dr. Richard Besser said, is that we may not be prepared for future, even more serious outbreaks of other viral diseases.

"I think we've been far too much in a reactive mode when it comes to new emerging infections," Besser said on "This Week." "There has to be a much bigger approach, a much bigger effort to try and look at where will the next virus emerge and how we get prepared for that wherever it may occur."

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