ATLANTA – The Ebola virus has killed more than 700 people in Africa and could have catastrophic consequences if allowed to spread, world health officials say. So why would anyone allow infected Americans to come to Atlanta?

The answer, experts say, is because Emory University Hospital is one of the safest places in the world to treat someone with Ebola. There's virtually no chance the virus can spread from the hospital's super-secure isolation unit.

And another thing, they say: Medical workers risking their lives overseas deserve the best treatment.

Dr. Kent Brantly became the first person infected with Ebola to be brought to the United States from Africa. He arrived Saturday at one of the nation's best hospitals. Fellow aid worker Nancy Writebol is expected to arrive in several days.

Centers for Disease Control Director Tom Frieden said he understands the public's concerns about Ebola, and the public health role is to ensure that the infection is not spread.

"Ebola is very deadly. And it's normal to be scared of deadly diseases," he said.

Emory's infectious diseases unit was created 12 years ago to handle doctors who get sick at the CDC. It is one of about four in the country equipped with everything necessary to test, treat and contain people exposed to very dangerous viruses.

In 2005, it handled patients with SARS, which unlike Ebola can spread when an infected person coughs or sneezes.

In fact, the nature of Ebola — which is spread by close contact with bodily fluids and blood — means that any modern hospital using standard, rigorous infection-control measures should be able to handle it.

Still, Emory won't be taking any chances.

"Nothing comes out of this unit until it is noninfectious," said Dr. Bruce Ribner, who will be treating the patients. "The bottom line is: We have an inordinate amount of safety associated with the care of this patient. And we do not believe that any health care worker, any other patient or any visitor to our facility is in any way at risk of acquiring this infection."

Ribner also said the patients deserve help.

"They have gone over on a humanitarian mission, they have become infected through medical care and we feel that we have the environment and expertise to safely care for these patients and offer them the maximum opportunity for recovery from these infections," he said Friday.

Amber Brantly was heartened to see her husband climb out of the ambulance that met his plane at Dobbins Air Reserve Base outside Atlanta. He climbed out dressed head to toe in white protective clothing, and another person in an identical hazardous materials suit held both of his gloved hands as they walked gingerly inside.

"It was a relief to welcome Kent home today. I spoke with him, and he is glad to be back in the U.S.," she said in a statement. "I am thankful to God for his safe transport and for giving him the strength to walk into the hospital."