A patient in London has been confirmed to be receiving treatment for rabies after being bitten by a dog in South Asia, the Health Protection Agency (HPA) said on Wednesday.

Rabies is normally transmitted through saliva from an infected animal, most often through bites. Dogs are the most common transmitter of rabies to humans.

The HPA said that an estimated 55,000 deaths by rabies happen each yeah, predominantly in South and South East Asia.

Professor David Brown, a rabies specialist at the HPA, said that rabies is "extremely rare in the United Kingdom," stating that there had only been four reported cases of the disease this millennium, all from infected dogs in other countries.

"All travellers to a rabies-endemic country should avoid contact with cats, dogs and other animals wherever possible as you cannot be certain that there is no risk. If you are bitten, scratched, or licked by a warm blooded animal you must take immediate action and wash the wound or site of exposure," Professor Brown added."

"Seek medical advice without delay even if you have been previously vaccinated."

The Director of the HPA, Dr Brian McCloskey, said, "it is important to stress that there is no risk to the general public" as a result of the case, "or to patients and visitors at the hospital."

Despite the thousands of annual cases, Dr McCloskey said that there have been on documented cases of human-to-human transmission of the disease.

Rabies is a disease that mostly affects the central nervous system, with initial symptoms involving anxiety, headaches and a fever before progressing to difficulty drinking (hydrophobia) and respiratory failure.

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