The Dallas hospital treating the lone US Ebola patient has said he is in a critical condition.
A spokeswoman for Texas Health Presbyterian Hospital issued a six-word news release about Thomas Duncan, saying: “Mr. Duncan is in critical condition.”
The hospital previously said Mr Duncan was being kept in isolation and that his condition was serious but stable.
He travelled from disease-ravaged Liberia to Dallas last month before showing symptoms of the disease.
He was treated and released from the hospital before returning two days later in an ambulance and being diagnosed with Ebola.
The US government previously called for calm over the single case of Ebola in the United States, seeking to reassure the American public that there is little chance of an outbreak of the disease.
At the same time, the military said it had begun a long-awaited aid programme for Liberia, with medical testing taking place at two new labs and the construction of treatment centres.