A young Cambodian woman has been hospitalised in Vietnam after showing symptoms of the bird flu virus  that has killed 52 people in Asia since 2003, a doctor said on Friday.

The 20-year-old woman from Cambodia’s Kampot province has been on a respirator with a high fever since Wednesday, Dr. Nguyen Van Hung told Reuters by telephone from the General Hospital in Vietnam’s Kien Giang province.

“We have X-rayed her twice and both results show her lungs have been seriously damaged,” he said, adding that samples from the patient had been sent for bird flu tests at Ho Chi Minh City’s Pasteur Institute.

The woman is from the same area where four people have died this year from bird flu, which hit Asia in late 2003. The deadly H5N1 virus has also killed 12 Thais and 36 Vietnamese.

Health experts fear the virus could mutate into a form that can pass easily among humans and trigger a global pandemic that could kill millions.