Tests are being carried out on another suspected ebola sufferer in the US - hours after a female nurse was confirmed to have contracted the disease from a patient.
The man was put into isolation in Boston, Massachusetts, after recently returning from Liberia - one of the countries worst affected by the outbreak.
It follows the death of 42-year-old Thomas Eric Duncan at a hospital in Dallas, Texas, the first from ebola on US soil.
A nurse who was treating Mr Duncan at the Texas Health Presbyterian Hospital was confirmed on Sunday to have been the first to contract the disease in the US.
The unnamed woman, who had been wearing full protective gear, reported having a "low-grade fever" on Friday and was then isolated, officials said.