OMAHA, Neb. (AP) -- An American health care worker who was exposed to the Ebola virus in Sierra Leone has not developed the disease and was released Thursday from a hospital in Nebraska.

Nebraska Medical Center (Eric Francis, Getty Images)

The health worker was monitored for 21 days, which is the virus' incubation period, the Nebraska Medical Center said in a news release. The patient arrived at the Omaha hospital's biocontainment unit on Jan. 4.

"The patient was regularly tested for the disease since arriving here in early January, and every test came back negative for Ebola," said Dr. Phil Smith, the biocontainment unit's medical director.

The hospital has not identified the patient at the patient's request.

The health worker said in the statement that the hardest part of the experience was "leaving my patients in Sierra Leone, who were some of the sickest I have ever seen." The health worker plans to return to West Africa at some point to continue helping treat those with Ebola.

Nebraska Medical Center treated three people with Ebola last fall.

Dr. Rick Sacra and freelance video journalist Ashoka Mukpo both contracted Ebola in Liberia and recovered after being treated at the Omaha hospital. Dr. Martin Salia, who contracted Ebola while working in Sierra Leone, was much more ill when he arrived in Nebraska and did not survive.

Sacra has said he's returning to Liberia.

The Ebola outbreak has claimed more than 8,600 lives, mostly in Sierra Leone, Liberia and Guinea.


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