Britain's Foreign Office says a nurse who recovered from Ebola has traveled to the U.S. to donate blood to an American patient who is fighting the disease.

William Pooley caught Ebola while working in Sierra Leone and was flown back to London for treatment, where he recovered. The American patient who received Pooley's blood wasn't identified.

Scientists think antibodies in the blood of people who have survived Ebola might help others infected with the disease. The Foreign Office said it arranged for Pooley to get an emergency passport. His original passport had been burned.

"This enabled him to fly out to the U.S. immediately and potentially assist with the treatment of an Ebola victim," the office said in a statement. Pooley's trip was paid for by the World Health Organization.