"Kent, bud. We got your test result. And I'm really sorry to tell you that it is positive for Ebola."

Those are the words that changed medical missionary Dr. Kent Brantly's life forever, as, after his efforts fighting the West African Ebola outbreak last year, he went from physician to patient.

It's a battle he documents in an upcoming memoir, co-written with wife Amber and excerpted for the Atlanta Journal-Constitution.

Kent writes of his reaction following the diagnosis, immediately asking, "'OK, so what is next? What's our plan? What are we going to do?'

"I am a doctor, trained to respond to a bad test result by creating a plan. More importantly, I am a husband and a father, and my thoughts turned to my beautiful wife and children back home in the United States. I might not see them, much less touch them, ever again.

"I stared out our bedroom window, looking to [my colleague]. 'How am I going to tell Amber?' "