WASHINGTON (AP) — The White House says it's looking into options for bringing back two American missionaries sick with Ebola in Liberia.

It would be the first time the disease was brought into the U.S.

Samaritans Purse Dr. Kent Brantly and Nancy Writebol, a missionary with the aid group SIM (S-I-M), remain in isolation. SIM USA President Bruce Johnson says Writebol is receiving an experimental drug.

White House Press Secretary Josh Earnest said that while the U.S. government would facilitate any transfer to the U.S., private companies would be used to transport them.

Late Thursday afternoon, officials at Atlanta's Emory University Hospital said they expected one of the Americans to be transferred there "within the next several days." The hospital declined to identify which aid worker, citing privacy laws.

The hospital has a special isolation unit built in collaboration with the Centers for Disease Control. It is one of only four facilities of its kind in the United States.

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