Nurse Nina Pham's Condition Is Improved

Nina Pham, the first Dallas nurse to contract Ebola, has had her health status upgraded from "fair" to "good," according to a statement released on Tuesday evening by the National Institutes of Health.

Pham was transfered last Thursday to the NIH Clinical Center in Bethesda, Maryland, from Texas Health Presbyterian Hospital, where she had contracted the disease. The NIH center is one of four hospitals in the coutnry with high-level containment rooms, and the staff there is trained to prevent the spread of diseases such as Ebola.

In late September, Pham helped care for Thomas Eric Duncan, the first person to be diagnosed with Ebola in the United States. Pham tested positive for Ebola on Oct. 12. A second nurse at the hospital tested positive for the disease a few days later.

It's still not clear how the nurses contracted the virus. However, some people have questioned the original guidelines from the Centers for Disease Control and Prevention on how to use personal protective equipment when treating Ebola patients. The agency announced on Monday (Oct. 20) that it had updated those guidelines to better protect workers. [2014 Ebola Outbreak: Full Coverage of the Viral Epidemic]

Ebola is spread through direct contact with the bodily fluids, such as blood or secretions, of an infected person, or by contact with contaminated objects, such as needles and syringes, according to the CDC. People with Ebola are contagious only after they start showing symptoms.

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