A British woman who contracted rabies after a dog bite in India has died in a London hospital.

The unidentified woman, said to be in her 50s, died over the weekend, Sky News reported.

"We regret to announce that a patient being treated for rabies by the Hospital for Tropical Diseases and colleagues at University College Hospital died over the weekend. The patient's family have kindly requested for the media to respect their privacy during this very difficult time and we will not be releasing any further details, nor will the family be making any statements," a spokesman for the hospital said.

Understood to be of Indian descent, the woman is said to have traveled to India without a rabies vaccine, The Sun reported.

She is thought to have been turned away by doctors in the UK three times before finally being diagnosed with the illness.

Another unrelated case of rabies is also being investigated by British authorities.

Rabies was eradicated from the UK over a century ago. Possibly life-threatening, it is an acute virus disease of the nervous system. Symptoms include abnormal behavior plus increased salivation, then paralysis and death if it goes untreated. It is prevalent in south and southeast Asian countries and is transmitted by saliva, usually through the bite of an animal.

The British Health Protection Authority says only four people in the UK have contracted the disease since 2009, compared to the 55,000 who die from it globally each year.