An Egyptian girl has died of bird flu, bringing the number of confirmed deaths from the disease in Egypt to 12, a World Health Organization official said on Monday.

"There was a case, 17 years old, from Fayyoum. She tested positive ... Unfortunately, she passed away," said Hassan el-Bushra, regional adviser for communicable diseases surveillance for the World Health Organization.

Bushra said the girl, identified as Nouri Nadi, was believed to have been infected after coming into contact with sick and dead birds.

The new case brings to 20 the number of people known to have been infected with bird flu in Egypt, which has the largest known cluster of human cases outside Asia. Twelve have died and eight others have recovered since the virus first surfaced in Egyptian poultry a year ago.

Bushra said the girl who died had started showing symptoms of the illness in late January, but initial tests indicated she had seasonal flu. Later tests were positive for the deadly H5N1 bird flu virus.

Neither Bushra nor the state news agency MENA, which also reported on the death, said when exactly the girl had died.

Most people infected in Egypt had been in contact with poultry kept at home. Bird flu initially caused panic across the country and did extensive damage to the poultry industry.

The Egyptian government said last month that poultry production had recovered to 1.8 million birds a day, just short of the 2 million produced before the outbreak.

TAMIFLU TREATMENT?

The latest death came several weeks after the World Health Organization said two people who died of bird flu in Egypt in December had a strain of the bird flu virus that has shown "moderate" resistance to the frontline antiviral Tamiflu.

Bushra said it was too early to tell if Nadi had been infected with the mutated strain, which killed a factory worker and his teenage niece in Gharbia province in the Nile Delta.

Bushra said he was unsure whether Nadi had been treated with Tamiflu at all, since early tests for bird flu in the girl were negative.

Known as "294S", the mutated strain was first detected in 2005 in a teenage girl in Vietnam who survived.

The WHO reaffirmed last May that patients should get Tamiflu as a frontline treatment for bird flu, but said in certain cases, doctors may consider using it along with amantadine, an older class of effective flu drugs.

Both Tamiflu and Relenza belong to a new drug class called neuraminidase inhibitors and can prevent the virus from infecting cells in the first place.