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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."

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Thomas Eric Duncan, the first patient to be diagnosed with Ebola outside of Africa during the ongoing epidemic, is being treated at a Dallas hospital. via Facebook

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."

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We have increased Emergency Department screening for approximately six weeks. Screening is also taking place at Parkland’s clinics. — Parkland Hospital (@ParklandHealth) October 1, 2014

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