The third U.S. Ebola patient is said to be improving and has received a serum made using the blood of an American patient who recovered.

Richard Sacra was transported back last week from Liberia after showing signs of infection, but it was revealed that he would have to recover without the aid of experimental Ebola drug ZMapp, since all supplies had been exhausted.

Doctors at the Biocontainment Unit in Nebraska said they were considering more conventional means to fight the disease, but mentioned that creating a serum from a recovered victim's blood might also be an option.

In addition to receiving the serum, which contained plasma from Dr. Kent Brantly, Sacra also was given another experimental drug, Reuters reports, though it hasn't been revealed what that drug might have been.

Information on the experimental drug is being kept under wraps for the moment since it is still in early developmental stages.

Still, though he is showing improvement, Dr. Phil Smith is preaching that joy over the serum or drug be tempered. "I don't know how much of his recovery is due to the drug, how much is due to the convalescent serum and how much to the aggressive intravenous fluids."

Brantly turned out to be a blood type match with the 51-year-old patient and donated his blood, which might contain antibodies to fight off Ebola, as soon as he was able. "I spoke to his wife," Debbie Sacra said. "We marveled that they had the same blood."