A teenage girl has become the first known person to survive rabies without a vaccination, say doctors.
The teenager was bitten by an infected bat
A team at the Children's Hospital of Wisconsin used an experimental treatment on 15-year-old Jeanna Giese.
She was admitted to hospital last month with advanced symptoms of the disease after being bitten by an infected bat at a church in September.
Doctors used a cocktail of drugs to protect the brain and nervous system from the effects of the disease.
They were able to diagnose the condition quickly because Jeanna was exhibiting classic signs of the disease, such as periods of unconsciousness, double vision and slurred speech.
The disease had progressed to a point where immunisation was not an option.
So a team of eight specialists used coma inducing drugs to protect the teenager's brain and a cocktail of drugs to protect her nervous system and boost her immune
Dr Rodney Willoughby, an expert in child infectious disease who led the team, said the aim was to protect the brain while the disease ran its course through the rest of the teenager's body.
Previous research has indicated that the virus tends to kill by damaging the brain tissues.
Jeanna lapsed into a coma within an hour of starting treatment.
After a week of treatment tests showed that Jeanna's immune system was creating antibodies to fight the virus.
Treatment eased off
The drug treatment was gradually eased off as the virus began to subside, allowing the teenager to regain consciousness.
Subsequent laboratory tests carried out by the US Centers for Disease Control and Prevention in Atlanta showed that the teenager had cleared the virus.
Dr Willoughby said Jeanna was now physically weak but regaining her strength and
voice after weeks of mechanical ventilation.
However, it is still too soon to say whether Jeanna will have long-term neurological
or physical problems.
"Jeanna is clearly alert and recognises her parents," he said.
"No one had really done this before, even in animals.
"None of the drugs are fancy. If this works it can be done in a lot of countries."
Only five people in the world before Jeanna are known to have survived rabies.
But they received standard treatment - a series of rabies vaccine shots - before experiencing symptoms.
The doctors say the treatment will have to be duplicated in another patient before it can be credited as a rabies treatment.
They have refused to reveal details of the exact drugs used until details are published in a medical journal.