OMAHA, Neb. (AP) — Officials at the Nebraska Medical Center say a doctor who became infected with Ebola while working in Liberia is communicating with caregivers as they decide on a course of treatment.

Officials say 51-year-old Dr. Rick Sacra is sick, but in stable condition. He's the third American aid worker sickened with the virus. The other two have recovered.

Sacra is being treated at a 10-bed special isolation unit built to handle patients with highly infectious and deadly diseases.

Sacra delivered babies at the Liberian hospital and was not involved in the treatment of Ebola patients, so it's unclear how he became infected with the virus that has killed an estimated 2,100 people during the outbreak.

The medical team is discussing experimental treatments, including using blood serum from a recovered patient. About a half-dozen drugs or vaccines are in development.

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