Updated

Laboratory tests confirmed that a 25-year-old woman who died in the Indonesian capital overnight had bird flu, officials said Wednesday as they investigated the possibility that several members of a family in West Java were infected by the virus.

Health experts are closely watching possible "clusters" of cases within families or neighborhoods for signs of human-to-human transmission of the virus.

Dr. Ilham Patu, a spokesman for Jakarta's infectious diseases hospital, said the government was waiting for the tests on the woman, who died late Tuesday or early Wednesday, to be confirmed by a World Health Organization-accredited laboratory in Hong Kong.

That could take several days. Until then, the government will keep its bird-flu death toll at seven.

The H5N1 bird flu virus has been ravaging poultry stocks across Asia since 2003 and has jumped to humans, killing at least 68, most in Vietnam and Thailand.

On Wednesday, China reported its 25th outbreak of bird flu in poultry since Oct. 19. China has confirmed three human cases of bird flu, including two fatalities.

Most human cases of the disease have been traced to contact with infected birds. But experts fear a human flu pandemic if the virus mutates into a form that passes easily between people.

Patu said authorities were alarmed by the deaths of two brothers of a 16-year-old who came down with bird flu in Bandung, the capital of West Java province.

The two boys died before doctors took samples from them, so it was not clear if they if they had been infected by the virus.

The 16-year-old remained hospitalized Wednesday.

"Whatever happens, he must get better," said his father, Dahli, who like many Indonesians uses a single name. "He is all I have left. He's my only hope."

Agricultural officials said they would test people and birds near the family's home to see if they had the disease. They noted that hundreds of chickens in the area had died.