Preliminary tests have found that bird flu killed two more siblings in Indonesia, officials said Friday, as the country grapples with a separate outbreak involving the largest family cluster ever reported.
Local tests found that a brother and sister from West Java who died earlier this week were infected by the H5N1 virus, said Nyoman Kandun, head of the Health Ministry's office of communicable disease control.
The tests will be sent to a World Health Organization laboratory for further confirmation.
WHO officials so far have confirmed 33 human deaths from bird flu in Indonesia, out of 124 worldwide.
The latest victims, an 18-year-old boy and his 10-year-old sister, died Tuesday in the state-run Hasan Sidikin hospital in Bandung, the capital city of West Java, said Achmad, an official at the ministry's special task force post for bird flu, who uses only one name. They died within hours of each other less than a day after arriving at the hospital, he said.
The newest cases come as Indonesia is struggling with a different family cluster in northern Sumatra in which six of seven family members died of bird flu, the most recent on Monday. An eighth family member who died was buried before tests could be done, but she was also considered to be among those infected with bird flu.
In other developments:
WHO officials have not been able to link the family members to contact with infected birds, and have said it's possible limited human-to-human transmission may have occurred. Similar isolated cases of transmission among humans is believed to have occurred in four or five other family clusters, said WHO spokesman Dick Thompson. But the Indonesia case is the largest ever reported.
However, WHO has stressed the virus has not mutated in any way and has shown no signs of spreading outside the family, all blood relatives who had very close contact with each other.
A team of international health experts and villagers is closely monitoring the area where the family lived in northern Sumatra to ensure no one else experiences flu-like symptoms.
About 30 people in the village of Kubu Simbelang have been asked to stay inside their homes and avoid close contact with others as a precautionary measure, Thompson said.
Experts also are exploring whether the first woman sickened in the family may have had contact with sick or dead chickens. She worked at a market where chickens were sold and may have used chicken feces as a garden fertilizer, WHO officials have said.
A special task force will be established to help slaughter birds in the affected area and carry out poultry vaccinations, said Aburizal Bakrie, coordinating minister for people's welfare. He said the government has allotted $961,000 to deal with the cluster in North Sumatra, while the health ministry has set aside $13.4 million for the national program.
Bakrie said anyone who hinders or resists efforts to control the bird flu virus could be jailed up to one year under a so-called law of epidemic.
The announcement comes after villagers in Sumatra refused to cooperate with health officials and some, in an act of defiance, beheaded a chicken and drank its blood earlier this week to try to prove that bird flu did not sicken anyone there.
Experts fear the H5N1 bird flu virus will mutate into a form that spreads easily among people, possibly sparking a pandemic. So far, the virus remains hard for people to catch, with most human cases linked to contact with infected birds.