Atlanta (CNN) -- The Ebola virus is coming to the United States for what's thought to be the first time, as two Americans return home after getting infected while helping others cope with the outbreak ravaging West Africa.
The patients will head to Emory University Hospital in Atlanta. One "will arrive in the next several days, and then a second patient will be coming a few days after that," according to Dr. Bruce Ribner, who oversees the Emory isolation unit where the pair will be treated.
"The patients have been evaluated, and (medical officials in Liberia) feel they are safe to transport," Ribner said of the two patients, who he later characterized as "stable."
The unit -- created in conjunction with U.S. Centers for Disease Control and Prevention, which is based down the road -- is designed to optimize the care for those with infectious diseases while safeguarding health care workers and visitors. Emory's hospital is one of only four U.S. institutions capable of such care, according to Ribner.
He pointed out many precautions in place to prevent the deadly virus from spreading. These include controlling everything that comes into and out of the unit, "special air handling" and windows and an intercom so that guests can interact with patients without being in the room.
As one of four physicians overseeing the patients' treatment, Ribner said, "I have no concerns about either my personal health or the health of the other health care workers who will be working in that unit."
Ebola isn't "some mystical pathogen (with) some bizarre mode of transmission," the doctor noted, adding that it is transmitted similar to illnesses like SARS or HIV.
But while the Emory staff members are confident, that doesn't mean they have experience dealing with Ebola, which the World Health Organization reports has infected more than 1,300 people and killed over 700 in recent weeks in Liberia, Sierra Leone and Guinea. In fact, no U.S. medical facility has had a known patient with the virus.
That's because, as Ribner points out, "this particular pathogen is new to the United States."
Special medical plane dispatched to Africa
The patients are health care workers themselves: Nancy Writebol and Dr. Kent Brantly were infected while treating Ebola patients in Liberia last month. They have been in serious condition for three days.
A medical charter plane that departed Georgia on Thursday will bring back one American at a time, starting with whoever is in the best condition to travel, said Todd Shearer, spokesman for Samaritan's Purse, the Christian aid group with which both are affiliated.
The plane is equipped to bring only one patient at a time, Shearer said Friday.
The isolative pod aboard the Gulfstream jet is called an Aeromedical Biological Containment System and looks like a tent. It contains multiple layers of isolation to prevent the patient from coming into contact with anyone, including caregivers inside the pod.
The Americans will arrive at Georgia's Dobbins Air Reserve Base before being transferred to the Emory hospital, Pentagon spokesman Rear Adm. John Kirby said.
The evacuation effort was in motion Friday, with the plane making a stop at the Azores' Lajes Air Base on Friday morning on its way to Liberia, according to Maria Francisca Seabra, a spokeswoman for Portugal's Ministry for Foreign Affairs.
Evacuations trigger fear in U.S.
After the evacuation plans were made public Thursday, social media in the United States lit up with fearful reactions. Many posts called for keeping the infected patients out of the country.
"As much as I respect the Samaritan's Purse workers with Ebola, I really don't want it anywhere near the US," a user posted to Twitter under the hashtag #EbolaOutbreak.
On the website of conspiracy talker Alex Jones, who has long purported that the CDC could unleash a pandemic and the government would react by instituting authoritarian rule, the news was a feast of fodder.
"Feds would exercise draconian emergency powers if Ebola hits U.S.," a headline read on infowars.com.
Yet Ribner repeatedly downplayed the risk that anyone who will be in contact with Brantly or Writebol is at risk. And the doctor noted that the two health care workers had put themselves at risk by going to Africa to help people in need.
"We have two individuals who are critically ill, and we feel that we owe them the right to receive the best medical care ... available to them," Ribner said, adding that the two will have a much better chance being treated in the United States than in Africa.
Although Ribner said there are discussions about offering "experimental protocols" to Brantly or Writebol, there is no specific treatment that has been approved by the U.S. Food and Drug Administration.
Rather, medical staff will offer "supportive care": doing whatever they can to treat symptoms tied to the virus, such as clotting issues or kidney failure.
"We depend on the body's defenses to control the virus," Ribner said. "We just have to keep the patient alive long enough in order for the body to control this infection."
Still, even if Brantly and Writebol don't spread Ebola in the United States, others might.
Many experts have said that other people will probably come to the country with Ebola at some point. It takes a while for symptoms -- which start out like many diseases, including common flus, with headaches, fever, nausea and diarrhea, then progress to abdominal pain and bleeding -- to break out. An infected person can get onto a plane feeling fine, then fall ill after landing.
The fight against Ebola
There is currently no vaccine available to prevent Ebola's spread, but one is in the works.
The National Institutes of Health announced that it will begin testing an experimental Ebola vaccine in people as early as September. Tests on primates have been successful.
The announcement came the same day as the CDC issued a Level 3 alert for Guinea, Liberia and Sierra Leone, warning against any nonessential travel to the region.
As of now, the outbreak has been confined to West Africa, but it is getting worse there. Although infections are dropping off in Guinea, they are on the rise in Liberia and Sierra Leone.
As infection accelerates, some aid groups are pulling out to protect their own.
Dr. Thomas Frieden, director of the CDC, said that even in a best-case scenario, it could take three to six months to stem the epidemic in West Africa.