(CNN) -- The young woman battling a flesh-eating bacterial infection in Augusta, Georgia, has taken another step toward recovery: Doctors have upgraded her condition from "serious" to "good."
The change indicates Aimee Copeland's "vital signs are stable and within normal limits," that she is "conscious and comfortable" and that indicators are "excellent," Doctors Hospital said in a news release Monday.
Copeland, 24, is doing so well that she got into a wheelchair and left her hospital room for the first time Sunday, her father wrote Monday on his blog.
"In your mind's eye, you probably are picturing Aimee grabbing a wheelchair and scooting into it by herself and then rolling herself through doorways and down hallways like some superhuman quad amputee," Andy Copeland wrote. "Dispel such notions. The process of actually sitting up requires the aid of a very good physical therapist, which we are fortunate to have."
Her father wrote that being outside was "the best therapy she has had in weeks."
Sitting among the pine trees, Andy and Donna Copeland asked their daughter how she really felt about the past 49 days, he wrote.
He wasn't expecting the response he got.
He wrote that she said she felt "blessed" -- not blessed to be alive, but blessed to be different.
"'I mean that I am blessed to have the opportunity to experience something that not many other people have the chance to experience,'" Copeland wrote, recalling his daughter's words. "'I am blessed to be able to have a challenge that not many others get to have. I am blessed to have the capacity to share my experience with others and have a chance to improve the quality of someone else's life. I'm blessed to be different.'"
Aimee Copeland's ordeal began May 1, when she was riding a makeshift zip line across the Little Tallapoosa River, about 50 miles west of Atlanta. The line snapped, and she fell and got a gash in her left calf that took 22 staples to close.
Three days later, still in pain, she went to an emergency room. Doctors eventually determined she had necrotizing fasciitis caused by the bacteria Aeromonas hydrophila.
The bacteria led surgeons to amputate most of her hands, part of her abdomen, one of her legs and her remaining foot in an effort to stay ahead of the infection. She has also had multiple skin grafts.
Her father has written regularly since about her situation, with over 78,000 "likes" on his Facebook blog devoted to Aimee's fight.
A number of bacteria that are common in the environment but rarely cause serious infections can lead to the condition. When the bacteria gets into the bloodstream -- such as through a cut -- doctors typically move aggressively to excise even healthy tissue near the infection site in hopes of ensuring none of the dangerous bacteria remain.
The infection attacks and destroys healthy tissue and is fatal about 20% of the time, according to the Centers for Disease Control and Prevention.
Dr. William Schaffner, chairman of the Department of Preventive Medicine at the Vanderbilt University Medical Center, estimates that fewer than 250 such cases occur each year in the United States, though estimates are imprecise since doctors do not have to report the cases to health authorities.