An American doctor infected with the deadly Ebola virus while in Liberia is back in the U.S. Dr. Kent Brantly is being treated at an Atlanta hospital, his wife grateful for his return. (Reuters)

An American doctor infected with the deadly Ebola virus while in Liberia is back in the U.S. Dr. Kent Brantly is being treated at an Atlanta hospital, his wife grateful for his return. (Reuters)

An American doctor stricken by Ebola in West Africa arrived home for treatment in Atlanta on Saturday, and U.S. government officials are urging the public to remain confident in the health-care system’s ability to keep the deadly disease isolated.

A charity organization, Samaritan’s Purse, said two Americans in serious condition with the disease were being evacuated: Kent Brantly, a Fort Worth doctor who had been treating Ebola victims in Liberia, and Nancy Writebol, a missionary from Charlotte.

Brantly and Writebol have been hospitalized in serious condition in Monrovia, the Liberian capital. Brantly was brought back to the United States first, in a specially equipped “air ambulance” aircraft that landed Saturday at Dobbins Air Reserve Base, in the northwest Atlanta suburbs, according to news reports.

He was being taken to Emory University Hospital in Atlanta, which has one of four facilities in the country designed to handle such cases.

Once at the hospital, one person in white protective clothing from head to toe climbed down from the back of the ambulance and a second person in the same type of hazmat-looking suit appeared to take his gloved hands and guide him toward a building at Emory, the Associated Press reported.

“The patients will be escorted throughout by specially and frequently trained teams that have sufficient resources to transport the patients so that there is no break in their medical care or exposure to others,” said Pentagon spokesman, Rear Adm. John F. Kirby.

The news of the return to U.S. soil of the two Ebola patients prompted a jittery response on social media, highlighting the special terror that the virus has come to carry for Americans familiar with movies such as “Outbreak” and the best-selling Richard Preston book “The Hot Zone.”

For example, there was a much-publicized tweet Friday from Donald Trump: “Stop the EBOLA patients from entering the U.S. Treat them, at the highest level, over there. THE UNITED STATES HAS ENOUGH PROBLEMS!”

Ebola is not nearly as contagious as many other pathogens, such as influenza, but it’s unusually lethal. This outbreak, easily the largest ever, began in Guinea in March and had killed 729 people as of Sunday, including about 60 percent of people who had come down with the infection, according to the World Health Organization.

There is no cure for the Ebola virus disease. Treatments are limited to such basics as keeping a patient hydrated. The virus can incubate for up to 21 days before symptoms appear. They include fever, vomiting, diarrhea, massive internal and external bleeding, and multiple organ failure.

But officials on Friday stressed that fears of an Ebola outbreak in the United States are unwarranted. A person infected with Ebola is not contagious until becoming sick. The virus spreads only through direct contact with bodily fluids. It is not an airborne contagion. There have been multiple outbreaks in Africa in the past, and they have all been contained through old-fashioned techniques of quarantining patients.

An infected person could potentially travel to the United States carrying the virus. To heighten vigilance, the Centers for Disease Control and Prevention sent health-care professionals a new set of recommendations Friday for handling patients who might be suspected of having the disease.

These include isolating patients in a private room, limiting visitors and requiring doctors and nurses to wear protective equipment, including a facemask, goggles or a face shield, double gloves and shoe covers.

“U.S. hospitals can safely manage a patient with Ebola following our recommended infection-control procedures,” said CDC infectious disease specialist David Kuhar.

“It’s important that we do not let fear of the unfamiliar overtake our reasoned approach to any infectious disease control,” said Barbara Reynolds, a CDC spokeswoman.

“There is zero danger to the U.S. public from these [two] cases or the Ebola outbreak in general,” said Amesh Adalja, an infectious disease doctor at the University of Pittsburgh Medical Center.

“People who have Ebola are not walking around on the street. They are very, very sick and pretty much confined to a hospital and to a bed,” he added.

This is the first time an Ebola patient has been brought to the United States, the CDC said. But it’s not the first time an ultra-

lethal virus like this has surfaced in the U.S. health system. The CDC said there have been five instances in which people came to the United States carrying the Marburg virus and Lassa fever virus, which, like Ebola, are in the family of viral hemorrhagic fever diseases. The health system correctly identified the disease in every case, and the virus didn’t spread, the CDC said.

“Ebola does not pose a significant risk to the U.S. public,” the agency concluded.

These assurances come just days before Washington will host a summit of African heads of state and their entourages. The leaders of Sierra Leone and Liberia have indicated that they may not attend, according to the White House.

President Obama on Friday addressed the outbreak and its effect on next week’s summit: “Folks who are coming from these countries that have even a marginal risk or infinitesimal risk of having been exposed in some fashion, we’re making sure we’re doing screening on that end as they leave the country. We’ll do additional screening when we’re here.”

He added, “Keep in mind that Ebola is not something that is easily transmitted. That’s why, generally, outbreaks dissipate. But the key is identifying, quarantining, isolating those who contract it and making sure that practices are in place that avoid transmission.”

It is self-evident that, in the era of modern aviation, a virus can go anywhere in the world within 24 hours. Nigeria is on alert because an American, Patrick Sawyer, a consultant for the Liberian Finance Ministry, collapsed in the airport on arriving in Lagos. He became sick during his journey from Liberia, which included stops in Ghana and Togo. Hospitalized on arrival in Nigeria, he died July 25.

His wife, Decontee Sawyer, who lives in Minnesota with their three daughters, said her husband’s death was a turning point for the outbreak in Liberia.

“People had been dying before Patrick, but nothing was being done. It took a government official to die in a foreign country for the Liberian government to wake up,” she said in a telephone interview Friday. “There were steps that could have been taken, the steps they are taking now, and maybe then Patrick would still be alive.”

The battle against the disease is getting new funding. The World Health Organization and the presidents of the West African countries affected by the outbreak launched a $100 million Ebola Virus Disease Outbreak Response Plan on Friday. The WHO said it has an urgent need for more doctors, nurses, epidemiologists and social mobilization experts.

“This outbreak is moving faster than our efforts to control it,” Margaret Chan, WHO director-general, said during a meeting Friday with the leaders of the three countries wrestling with the Ebola outbreak — Guinea, Liberia and Sierra Leone.

She said it would be “extremely unwise” to allow the disease to continue its march through local populations.

“Constant mutation and adaptation are the survival mechanisms of viruses and other microbes,” Chan said. “We must not give this virus opportunities to deliver more surprises.”

The biggest problems are people “running away” from the specialists who are trying to monitor them, usually because they are in denial about being exposed, or afraid of the stigma of having the disease, said Peter Clement, adviser on disease prevention and control for the WHO in Monrovia. People are burying their dead on their own, causing additional and needless exposure, he said.

Anyone thought to be exposed is monitored daily by volunteers, but sometimes the residents flee.

“People hide in the rural areas, do the burials,” Clement said in a telephone interview. “The fear and the panic — but now there is stigma, too. And so they hide.”

The international aid group Doctors Without Borders said Friday that it had more than 550 staff members working to stem the outbreak. But despite adding dozens of new beds to a treatment center in Sierra Leone, the organization has been overwhelmed. In Liberia, the situation is “dire” and there is “almost no capacity on the ground to respond,” the organization said in a statement.

One of the biggest challenges has been rumor control. There has been a surge of mistrust and hostility aimed at the international medical teams.

Leisha Nolen, a 37-year-old “disease detective” for the CDC who spent a month this spring in Liberia, said she plans to head Saturday to Sierra Leone for a month-long mission tracking people who may have come into contact with Ebola victims. These people can be quarantined if they show any symptoms of the disease.

But she said health workers struggle to gain the trust of people who are skeptical and scared.

“A lot of people in West Africa right now don’t know what to believe or who to believe,” she said. A major hurdle, she said, is “getting people to accept this idea of what the infection is, and that it is a true infection and not some sort of way to trick them or take advantage of them by the government or by the foreigners.”

Lenny Bernstein, Ariana Cha and Karen DeYoung contributed to this report.