After spending weeks in Emory University Hospital's isolation unit, the American Ebola patients are almost ready to start their recovery.

Dr. Kent Brantly and Nancy Writebol contracted Ebola while doing missionary work in Liberia. The two patients have been hospitalized in Atlanta since early August.

However, they are almost at the end of the 21-day period during which they are contagious. They will soon be able to leave the isolation unit and work on getting back to full health.

The patients will no longer have to worry about infecting others or getting infected again.

"They're immune," said Rob Dretler, M.D., of Infectious Diseases Specialists in Atlanta.

They ultimately will be able to go back to their mission posts, if they wish, and continue their fight.