CDC confirms first Ebola case in the United States

The Center for Disease Control and Prevention has confirmed the first case of Ebola diagnosed in the United States. The unidentified adult is being treated at a hospital in Dallas.

The patient left Liberia on Sept. 19 and arrived in the United States on the 20th, according to a CDC briefing held Tuesday evening. The patient began developing symptoms on the 24th, initially sought care on the 26th, and was then admitted into strict isolation at Health Presbyterian Hospital Dallas on the 28th.

The hospital says it is following CDC recommendations to keep staff safe.

The CDC is working to identify anyone who has come in contact with the newly-diagnosed patient. State health officials say no other cases are suspected in Texas.

They declined to comment if the patient was a U.S. citizen or if he flew on a commercial plane.

The CDC also sought to calm fears of an outbreak in the United States Tuesday. President Obama has been briefed on the situation.

“There is no doubt in my mind that we will stop it here,” CDC director Thomas Frieden said in the press conference.

“This is not Africa,” Zachary Thompson, director of Dallas County Health & Human Services, told WFAA. “We have a great infrastructure to deal with an outbreak.”

Jason McDonald, spokesman for the CDC, said health officials use two primary guidelines when deciding whether to test a person for the virus.

“The first and foremost determinant is have they traveled to the region (of West Africa),” he said. The second is whether there’s been proximity to family, friends or others who’ve been exposed, he said.

Shares of companies working to develop an Ebola vaccine rose after the news broke.

The CDC has said 12 other people in the U.S. have been tested for Ebola since July 27. Those tests came back negative. Four American aid workers who have become infected while volunteering in West Africa have been treated in special isolation facilities in hospitals in Atlanta and Nebraska, and a U.S. doctor exposed to the virus in Sierra Leone is under observation in a similar facility at the National Institutes of Health.

Ebola is believed to have sickened more than 6,500 people in West Africa, with the vast majority of the cases in Liberia, Guinea and Sierra Leone. More than 3,000 deaths have been linked to the disease, according to the World Health Organization.

Earlier today, the CDC hinted that the Ebola outbreak in Nigeria and Senegal could be nearing an end.

The Associated Press contributed to this report.