A mosquito-ravaged backpacker missing for more than a week in WA’s remote Wheatbelt has been found alive.

German national Carolina Wilga, 26, was located “safe and well” on Friday afternoon, 12 days after she was last seen outside a general store in Beacon, more than 300km northeast of Perth.

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A stranger made the miracle discovery by the boundary of the 300,000-hectare Karroun Hill Nature Reserve, and she is now on a police plane flight to Perth for treatment.

“She’s been located walking on a bush track on the edge of the reserve from which she was missing and she’s been recovered by a member of the public — which was fantastic,” Inspector Martin Glynn said.

“She’s been brought down here to Beacon and is now en route to a hospital in Perth for some medical attention.

“As you can imagine from the trauma she’s suffered for the last few days, she’s been through a great deal.

“She does have some injuries — she’s been ravaged by mosquitoes, she’s obviously been through an amazing journey of trauma.”

Wilga’s family overseas, who first raised the alarm, have been told that she is alive.

Glynn said “you’re always hopeful” of an outcome like this.

“I think once we do hear her story, it will be a remarkable story. She’s obviously coped in some amazing conditions,” he said.

“It’s a really, really challenging environment to cope in and the weather conditions have been really adverse with temperatures getting down to zero (degrees) at night, there’s been rain, there are reports of all sorts of challenges in that terrain for searchers.

“It must have been a thousand times worse for her in her condition when she left ... that vehicle.”

WA Premier Roger Cook said the news Wilga had been found was “nothing short of remarkable”.

“I’m incredibly relieved to confirm that Carolina Wilga has been found alive this afternoon after twelve long days missing in WA’s outback,” he said.

“This news is nothing short of remarkable.

“To our emergency services and everyone who searched, shared information, and supported the family through this ordeal — thank you.

“We’re yet to have the full picture of what happened, but tonight, we can all breathe a little easier knowing Carolina is safe and well.”

Wilga has been backpacking around Australia for the past two years, working most recently at regional mine sites in WA.

She had also been staying at backpackers and hostels during her visits to Perth.

She had not been heard from since June 29, when she was seen on CCTV visiting the general store in Beacon, northeast of WA’s capital city.

She had also travelled solo through Toodyay a day earlier — with police also releasing vision of her stopping at a service station at about 4.30pm, smiling as she paid with her phone — and Dowerin.

Agencies around the country were alerted and the search at one point was a national one after friends and associates told police she may have planned to travel interstate to the east coast.

But that search zone was narrowed right down when Wilga’s van was found bogged at the bottom of a rocky outcrop on Thursday in Karroun Hill, about 40km away from her last sighting.

Police said she had made “extensive efforts” to get her recently purchased 1995 Mitsubishi Delica out of trouble, with no luck.

“(The van) was located in very heavy and quite challenging terrain,” Glynn said in an earlier update.

“She’d used Maxtrax and pieces of wood to try to free the vehicle from its location but unfortunately it was unsuccessful.”

Aerial assets including helicopters, planes and drones had taken to the sky in the search for her

Trackers were also sent to the area but recent rain and firm ground made it difficult to pick up which way she had set off.

The inspector said the area was a “wonderful class A nature reserve” but not one of the “classic visiting areas”.

“There are several others which include outcrops of rock, that are very much part of the tourist trail, but certainly this one wouldn’t be one that people would visit normally,” Glynn said.