An 8-year-old Cambodian girl has died of the bird flu, raising the country's death toll from the deadly disease to three, officials said Sunday.

Ly Sovann, director of the Health Ministry's Communicable Disease Control office, said the girl died Thursday at a Phnom Penh hospital. Tests showed she had the potent H5N1 (search) virus, which has killed at least 51 people in the region. Most human cases have been traced to contact with sick poultry.

He said the girl was from Cambodia's southwestern province of Kampot (search), where the country's two previous bird flu victims died.

Megge Miller, an epidemiologist working with the World Health Organization (search) in Cambodia, confirmed that the girl died from the H5N1 strain.

Two previous victims of bird flu were a 25-year-old woman and a 28-year-old man. The woman died in a hospital in neighboring Vietnam in January and the man died at a hospital in Phnom Penh last month.

The bird flu began ravaging poultry farms across Asia in December 2003. Thirty-six people have died in Vietnam and 12 in Thailand.

Health experts have warned the virus could mutate, increasing the risk of human-to-human transmission, which could spark a pandemic. However, there has been no evidence of that so far.