There is no cure for the Ebola virus ravaging West Africa, and it kills most of those it infects. But when Bruce Ribner got the call that two Americans stricken with Ebola were headed to his hospital, he did not hesitate.

"I said, 'Hey, we've been practicing for this for 12 years,'" he said.

Ribner is an infectious disease specialist who oversees the isolation ward at Emory University Hospital, which is designed to house people suffering from highly lethal illnesses that could decimate a population if not contained.

Two nurses who form part of the team trained to work in the ward canceled vacations to treat the patients.

And on Saturday, team members in hazmat suits stood by as a convoy accompanying the ambulance carrying patient Kent Brantly arrived at Emory after an overnight air ambulance flight from Liberia.

The driver of one vehicle flashed a victory sign as the convoy turned onto the hospital grounds. A medical worker, whose hazmat suit included a protective hood and mask, clambered out of the rear of the ambulance. Then Brantly, also wearing a special suit, carefully lowered himself to the ground. He leaned on the medical worker as they walked slowly through a door into the isolation ward.

Nancy Writebol was expected to arrive from Liberia this week on the same air ambulance that carried Brantly. Brantly, a doctor, and Writebol, a missionary, became sick last week while working in Liberia and treating others infected with Ebola.

"It was a relief to welcome Kent home today," his wife, Amber Brantly, said in a statement released through Samaritan's Purse, the aid agency Brantly was working with in Africa. "I spoke with him, and he is glad to be back in the U.S. I am thankful to God for his safe transport and for giving him the strength to walk into the hospital."

Although Brantly was able to walk, albeit with assistance, he remains seriously ill; the virus has no cure and a mortality rate as high as 90%, depending on the strain.

Ribner said the high-stakes mission to bring Brantly and Writebol home was born as much out of medical duty as humanitarian obligations. Their chances of survival were lower in Africa than in this country, where they will receive the kind of care that could enable their bodies to recover enough to fight off the virus.

"The critical component … is supportive care," Ribner said. "We're talking about maintaining blood pressure. We're talking about supporting respiration up to and including a respirator if the condition becomes that severe. People with Ebola virus infection may have kidney failure, so we are potentially talking about dialysis."

There is no other treatment for Ebola, which is named after the river running through the region in Africa where it was discovered in 1976. Until Saturday, the virus had never entered the United States.

But opposition to its importation via the ailing patients has been minimal, limited mainly to right-wing pundits and individuals griping on social media or eyeing the media horde bivouacked outside Emory.

"They're getting more than they bargained for," one man, Jeremy Eagins, said of the medical experts as he walked near the hospital, which is less than a mile from the Centers for Disease Control and Prevention headquarters. "We don't even know what's coming over our southern borders. We shouldn't be bringing something like this in."

"KEEP THEM OUT OF HERE," Donald Trump tweeted.

But there was no sign of fear, anxiety or opposition around Emory on Saturday, and Ribner said there never was, from the moment staff learned of the patients' imminent arrival.

"Everybody at Emory is extremely supportive of this mission," Ribner said. "We realize it's an important part of being an advanced healthcare facility."

U.S. Rep. Adam B. Schiff (D-Burbank), speaking on CNN, said the fact that Brantly and Writebol had a potentially deadly illness should not bar them from entering the country. "I don't think we should be so spooked because of the novelty of this terrible virus that we turn our back on Americans who are troubled," he said.

Ribner agreed.

"We have two individuals who are critically ill, and we feel we owe them the right to receive the best medical care which is available to them," he said.