The first patient undergoing treatment for Ebola at Emory, Dr. Kent Brantly, issued a statement Friday from his isolation unit saying he was "getting stronger every day."

Brantly arrived by special flight from Liberia last Saturday, igniting a nationwide debate. He is receiving treatment at Emory University Hospital with fellow missionary Nancy Writebol, in separate isolation rooms.

The statement follows recorded comments released this week by Writebol's husband, David Writebol. Like Brantly, Writebol expressed deep gratitude for the care the two are receiving at Emory.

Writebol also said he found it “astonishing” that some critics here were saying the two patients knew what they were getting into when they went to treat patients in Africa and should have stayed there when they got infected.

Brantly said he did not go to Africa knowing he was wading into an Ebola outbreak.

“My wife Amber and I, along with our two children, did not move to Liberia for the specific purpose of fighting Ebola,” Brantly wrote. “We went to Liberia because we believe God called us to serve Him at ELWA Hospital.” Later their work turned more and more toward Ebola, he said.

“I held the hands of countless individuals as this terrible disease took their lives away from them,” Brantly wrote.

When he first noticed symptoms in his own body, he said, he immediately isolated himself, and the diagnosis was confirmed three days later.