Rick Sacra, one of the American doctors infected with the Ebola virus while working in Liberia, is in stable condition. Sacra landed in the U.S. Thursday and moved to an isolation unit in a Nebraska hospital, where officials said he is communicating with medical staff.

Doctors at the University of Nebraska, where Sacra is being held at the Nebraska Medical Center’s special biocontainment unit, told reporters the 51-year-old is “sick but stable” and is receiving treatment to ensure that fluid loss and electrolyte loss do not impact his organ functions.

“Our patient is sick but stable and we are taking appropriate care of this patient,” Dr. Mark Rupp, chief of infectious diseases at the Nebraska facility, told a press conference. “We know that he is seriously ill with a virus that has a very high mortality associated with it. We are looking for alternatives to some of our experimental therapeutics right now.”

Sacra hails from the Boston area and previously spent 15 years working at a Liberia hospital only to return there upon learning that two other American aid workers, Kent Brantly and Nancy Writebol, had contracted the illness. Exactly how Sacra fell ill remains unknown, though, as multiple outlets have reported that he helped deliver babies during his time there and did not work with Ebola patients.

Insight on Sacra’s condition comes on the same day that the World Health Organization announced the death toll of the current Ebola outbreak in West Africa has reached 2,097 people (of the 3,944 known cases). The ongoing crisis is the worst in Ebola’s history, with officials admitting they’re nervous 20,000 people could be infected before the outbreak subsides.