According to physicians from the National Institutes of Health Clinical Center in Bethesda, Md., the condition of the U.S. patient with Ebola virus disease has improved from critical to serious.
No additional details about the patient were released.
The NIH also announced the Ebola virus circulating in West Africa has undergone relatively few mutations that would make it more severe or transmissible.
"The Ebola virus in the ongoing West African outbreak appears to be stable — that is, it does not appear to be mutating more rapidly than viruses in previous Ebola outbreaks, and that is reassuring," said Anthony S. Fauci, MD, director of the National Institute of Allergy and Infectious Diseases branch of NIH.
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