An Egyptian woman died of bird flu on Sunday, hours after tests confirmed she and two other members of her extended family had been suffering from the highly pathogenic virus, a World Health Organization official said.

WHO regional adviser for communicable diseases surveillance Hassan el-Bushra said the 30-year-old woman had been in hospital since December 17, but doctors had not immediately suspected bird flu as she denied having had contact with poultry.

The woman was part of an extended family of 33 living in a single house in a village near the town of Zifta in Gharbiya province, about 80 km (50 miles) north of Cairo, and was the third family member diagnosed with bird flu in 24 hours.

Earlier on Sunday, Bushra confirmed that two siblings from the same house, a brother, 26, and sister, 15, had the virus.

Bushra said the family raised ducks in their home, and the brother and sister had slaughtered the flock after a number of ducks had become sick and died.

When officials realized the woman was part of the same family, they tested her for bird flu and confirmed that she was infected with H5N1, and she was moved to a Cairo hospital, but died shortly thereafter.

The two siblings are in hospital in Cairo and have been treated. The rest of the family is under close medical surveillance, Bushra said.

Her death brings the number of total human deaths from H5N1 in Egypt to eight, and the number of human cases to 18 since the virus first surfaced in Egyptian poultry in February.

The initial bird flu outbreak caused panic in Egypt, where poultry is a major source of protein, and poor families frequently breed chicken and ducks domestically in cities and rural areas to supplement their diet and income.

The Egyptian cabinet announced in November that the country´s poultry production had recovered to almost the same level as before the deadly virus surfaced in February.

An official with the Food and Agriculture Organization had said in October that the onset of cooler weather could cause a flare-up of cases in poultry.