The man diagnosed with Ebola virus in Dallas first started feeling ill on September 24 and he showed up at Texas Health Presbyterian Hospital on September 26th, complaining of fever and abdominal pain.

 

The hospital had just been through a drill for such a case — a traveler from West Africa with potential symptoms of Ebola, which can include fever, although a stomach ache is not one of the classic symptoms. The patient, now identified as Thomas Eric Duncan, told a nurse he had come from West Africa, says Dr. Mark Lester, a vice president for the hospital system.

 

Yet somehow — it is not entirely clear yet how — Duncan was sent home. The “overall clinical presentation” didn’t suggest Ebola, Lester says.

 

Duncan returned two days later, on Sept. 28, in an ambulance. This time, the hospital staff treated him as an Ebola case and used all the right precautions to protect themselves from infection and to keep him away from other patients.

 

The two days that Duncan was sick and not isolated will be key to whether Ebola spreads in the United States.

 

The Centers for Disease Control and Prevention has issued very clear guidance — patients who have recently been in West Africa should be considered as potential Ebola patients. CDC says it’s been asked about 98 such cases by local or state health departments during the current Ebola epidemic, and considered 13 of them serious enough to justify running an Ebola test. Just one — the patient in Dallas — came back positive.

 

Still, should the emergency department have flagged Duncan on Sept. 26?

 

"People make mistakes."

“Unfortunately those things happen. That's human nature. People make mistakes,” said Dr. Anthony Fauci, head of the U.S. National Institute of Allergy and Infectious Diseases. "The CDC has been trying very hard to get the message out with a variety of announcements that if you're in a health facility, in an emergency room or clinic, and someone comes in with symptoms that are compatible with Ebola that do a simple travel history, just ask them the question. Have you done any foreign travel lately?” Fauci told MSNBC.

 

“And obviously, if someone would say I've been to Liberia or a West African country, that would be a big red flag. Unfortunately, that did not work in this case. It's a lesson learned. And hopefully, that won't happen again.”

 

During the two days, the patient returned to relatives he had been staying with in Texas. And now health officials say five school-aged children, as well as other people, may have been in close enough contact with him to be at risk.

 

Contact doesn’t equal infection, and the children will be watched for 21 days — the longest possible incubation period — to make sure they don’t become ill. At the first sign of a fever, they’ll be isolated and tested. CDC says it's confident everyone who Duncan might have infected has been found and will be watched, and that Ebola won't spread widely.

 

Ebola is not easy to catch. It’s worrisome because it’s so deadly — 70 percent of people sickened in this epidemic have died, according to the World Health Organization. But patients do not become contagious until they have symptoms and people must be in close contact with a patient or bodily fluids such as blood, feces or vomit, to catch it.

 

"We think it very unlikely that any health worker was exposed on Friday and certainly none since Sunday."

 

Dr. Edward Goodman, the epidemiologist at Texas Health Presbyterian Hospital, says Duncan was not vomiting or showing signs of diarrhea when he came in on the 26th, and by the 28th, the hospital and ambulance crew who carried him there were geared up. “We think it very unlikely that any health worker was exposed on Friday and certainly none since Sunday,” Goodman told a news conference.

 

“When the patient arrived on Sunday the 28th of September, he was received as a possible case,” Goodman added. “He was placed in the appropriate isolation.”

 

Health experts also point out that Ebola patients may not be especially infectious in the first few days of illness, because it takes a while for the virus to multiply in the blood and organs. CDC director Dr. Tom Frieden says many patients test negative for Ebola when they first get sick, because there’s not enough virus there to show up on the test and, presumably, not enough to make it easy to catch it from them.

 

Goodman stressed this, also. “In the first three to four days of symptoms the viremia is very low,” he said.

 

The first person diagnosed with the Ebola virus in the U.S. wasn't appropriately treated for suspected infection until after a relative personally called the Centers for Disease Control and Prevention, his nephew told NBC News on Wednesday night.

 

Health officials have acknowledged that Thomas Eric Duncan, 42, was initially sent home from Texas Health Presbyterian Hospital in Dallas when he showed up on Sept. 26 complaining of fever and abdominal pain. He had to return two days later in an ambulance.

 

That was the day "I called CDC to get some actions taken, because I was concerned for his life and he wasn't getting the appropriate care," Duncan's nephew, Josephus Weeks, told NBC News on Wednesday night. "I feared other people might also get infected if he wasn't taken care of, and so I called them to ask them why is it a patient that might be suspected of this disease was not getting appropriate care?"

 

Weeks added that he hoped "nobody else got infected because of a mistake that was made."

 

Weeks said the CDC referred him to the Texas Department of Health and Human Services, which spoke to him and then took appropriate action. "I called the CDC and they instructed me of the process, and that got the ball rolling," Weeks said.

 

A CDC spokesman told NBC News the agency could neither confirm nor deny Weeks' account. The hospital did not immediately respond to a request for comment.

 

Duncan, a Liberian national, may have contracted the virus in Liberia while taking a deathly ill neighbor to the hospital four days before he flew to Dallas to visit family members, The New York Times reported.

 

"I'm not angry," Weeks said. "It's more frustration and concern. ... I'm hoping that he can get the same kind of treatment that was given to the four other patients that survived, and that's my concern, and that's why I'm still asking about it."

 

As for Duncan, who was reported to be stable in serious condition, "he's still in pain," Weeks said. "He's doing all right. He's a fighter. I think our prayers, all together, will help him pull through."

 

BY MAGGIE FOX

NBCNews