Sept. 9, 2012 -- Sierra Jane Downing, the 7-year-old Colorado girl who contracted the bubonic plague while camping with her family, has now taken her first steps since fighting for her life in a Denver hospital and is expected to leave the hospital, and the rare disease, behind her.
Downing came upon a half-eaten squirrel while on a picnic at a campground with her family on Aug. 19 in Pagosa Springs. Though her parents told her no when she asked if she could bury the animal, Sierra Jane went back to the squirrel, put her sweatshirt down next to it, and then picked up the sweatshirt and put it around her waist.
Five days later, Sierra Jane was found by her parents on the bathroom floor. After she had a seizure and her breathing stopped, her parents rushed her to the local hospital. When doctors at the local hospital were left stumped over what was wrong with her, Sierra Jane was airlifted to Rocky Mountain Hospital for Children in Denver.
"I thought, 'oh my gosh we're going to lose her.' I was very concerned," Darcy Downing, Sierra Jane's mother told ABC News.
When she arrived at 5 a.m. the next day she still very sick but stable, so doctors placed her in the hospital's intermediate care unit under continuous monitoring. By 6:30 p.m. Saturday, Sierra Jane's condition had worsened and she was transferred to pediatric ICU for septic shock.
"I remember leaving that morning very scared that when I came back that night she wasn't going to survive," Dr. Jennifer Snow said.
Snow conferred with the hospital's infectious disease specialist Dr. Wendi Drummond about new clues: an unusually swollen lymph node in Sierra Jane's leg, along with bug bites.
That's when Sierra Jane's parents remembered the family trip to the campground.
"That was my eureka moment," Snow said.
Doctors suspect fleas jumped from the squirrel to Sierra Jane, infecting their young host with bubonic plague -- the same Black Death that killed 25 million people in the Middle Ages. But with an average of only seven U.S. cases per year, it's a disease doctors rarely see.
"There's a saying in medicine: if you hear hoof beats, look for horses," Dr. Drummond said. "But you don't want to forget about the zebras -- the more unusual, uncommon diseases. And in this case, this is a zebra.
Thanks to the doctor's quick thinking and starting Sierra Jane on a course of gentamicin, an antibiotic used to treat many types of bacterial infections, the girl will make a full recovery, and should leave the hospital tomorrow.
"They set her on my lap and she just melted into me and she said, 'Mommy, it feels so good to be held,'" Darcy Downing said as she leaned down to kiss Sierra Jane as she was sleeping. "That was the best moment. The best."