ATLANTA — As one of few Ebola survivors with medical expertise, Dr. Kent Brantly seems keenly aware of the position his painful experience has put him in. He hasn't spoken yet about his plans, but spent much of his first public appearance pleading for help for countries still struggling with the virus. "I am forever thankful to God for sparing my life and am glad for any attention my sickness has attracted to the plight of West Africa in the midst of this epidemic," Brantly said Thursday before leaving Emory University Hospital, where he and a medical missionary colleague spent three weeks in an isolation unit as they recovered.