The condition of an American healthcare worker being treated for Ebola at the National Institutes of Health has worsened, officials announced Monday.
In a statement posted on the NIH website, the agency said the patient's status has worsened from serious to critical.
The patient has not been named, but has been identified as a clinician working with Partners in Health, a Boston-based nonprofit organization. The group has been treating patients in Liberia and Sierra Leone since November.
The patient was flown on a chartered plane from Sierra Leone and arrived at the NIH campus in Bethesda, Md., on Friday. Three other healthcare workers from the same Sierra Leone facility arrived in the Washington area Sunday to be near the NIH campus in Bethesda in case they need treatment for Ebola.
The latest NIH patient is the 11th person with Ebola to be treated in the United States. Two patients have died; both contracted the illness in Africa.
Thomas Eric Duncan was treated in Dallas after contracting the virus in Liberia and died Oct. 8. He transmitted the disease to two nurses, who were treated and recovered.
Martin Salia, a surgeon, contracted Ebola in Sierra Leone and died in November after being admitted in extremely critical condition to Nebraska Medical Center's Biocontainment Unit in Omaha.
In addition to those in the Maryland area, at least nine other healthcare workers at Partners in Health were in the process of being brought to the United States for Ebola monitoring.
Four were headed to Emory University Hospital in Atlanta, where one arrived Friday.
On Saturday, four health care workers arrived at the Nebraska Medical Center. A fifth was expected to arrive Monday for monitoring, the facility said.
One of those being monitored in Nebraska has developed symptoms of Ebola and was being moved to the Biocontainment Unit, hospital officials said in a news release Monday.
"At this point, this person has not tested positive for the Ebola virus," Dr. Phil Smith, medical director of the Biocontainment Unit at Nebraska Medical, said in the statement. "However, because of a change in symptoms, we decided the most prudent course of action was to bring the individual to the Biocontainment Unit, where we can better monitor symptoms and safely perform testing. However, some of the symptoms which prompted the move to the Biocontainment Unit have resolved this morning."
In all, three patients with Ebola have been treated at Nebraska Medical. Dr. Richard Sacra was treated and released in September and NBC cameraman Ashoka Mukpo was treated and released in October.
The World Health Organization estimates that Ebola has killed more than 10,000 people, mostly in the West African nations of Guinea, Liberia and Sierra Leone in the current outbreak, the largest to date.