Two-year-old Falak, who was brought to a hospital in a battered condition, is fighting a grim battle for life as her brain has been affected by an infection, an AIIMS doctor said on Wednesday.

"Her conditon is very critical as she has developed infection in the brain. This has brought down her chances of survival to less than 50 per cent," Neurosurgeon with Jai Prakash Narayan Apex Trauma Centre of AIIMS, Dr Deeepak Agarwal, said.

Admitted in the Intensive Care Unit of the hospital since January 18, this badly bitten and battered baby girl has already undergone three life saving surgeries till now.

"Today in the wee hours, doctors drained out the rest of the water that had accumulated in her brain through the spine.

The fluid sample was sent to the laboratory for culture and after the reports came in, we started administering appropriate antibiotics for fighting the infection," he said.

"The next 24 to 48 hours are crucial. All will depend on how she is responding to the treatment," Dr Agarwal said.

Baby Falak was brought to the hospital with severe head injury, both her arms broken, bite marks all over her body and her cheeks branded with hot iron.

She was brought to the hospital by a teenage girl who claimed to be her mother and had cited a fall from the bed as the reason for the child's pathetic state.

Doctors said, "Though she is deeply unconscious and on the ventilator, she opens her eyes and makes limb movements only when given painful stimulus.

"This is part of the treatment module to check her brain functioning time-to-time," they said.

A case of sexual abuse has been ruled out after a gynaecologist carried out test on her a few days back, they said.

Forensic scientist are yet to verify if the marks on her body are that of human bite, Dr Agarwal said.