Hungry, thirsty and covered in insect bites, Wilga was airlifted to a Perth hospital for treatment after she was found on Friday.
The backpacker had lost hope of being rescued, police said.
“She spent 11 nights exposed to the elements and survived by consuming the minimal food supplies she had in her possession, and drinking water from rain and puddles,” Western Australia police said last week.
“She sought shelter at night where possible, including in a cave.”
Wilga was suffering from exhaustion, dehydration, sunburn, “extensive insect bites”, and an injured foot, police said.
The driver who spotted her, Tania Henley, told public broadcaster ABC that she saw Wilga waving her hands by the side of the road.
She appeared to be in a “fragile state”, bitten by midges and suffering from the cold.
“Everything in this bush is very prickly. I just can’t believe that she survived. She had no shoes on, she’d wrapped her foot up,” Henley said.
Until her rescue, she had been last seen on Jun 29 arriving in the van at a general store in Beacon.