KUBU SIMBELANG, Indonesia – Chickens ran free through this village framed by high mountains and rich fields of chilies, oranges and limes.

No health workers could be seen Saturday in the rural hamlet of Kubu Simbelang where at least six relatives died in the largest case to date of humans infecting each other with bird flu.

But as a precaution, the World Health Organization has put the maker of the anti-viral drug Tamiflu on alert for possible shipment of the global stockpile for the first time, officials said Saturday.

No further action regarding the global stockpile was expected for now, according to the WHO, which called the alert part of its standard operating procedure when it had “reasonable doubt” about possible human-to-human transmission.

“We have no intention of shipping that stockpile,” WHO spokesman Dick Thompson cautioned. “We see this as a practice run.”

Meanwhile, Indonesia confirmed three more bird flu deaths as the country grappled with a spike in human cases.

Bird flu has killed at least 124 people worldwide since the virus began ravaging Asian poultry stocks in late 2003.

A precautionary 9,500 treatment doses of Tamiflu from a separate WHO stockpile, along with protective gear, were flown into Indonesia on Friday. The tablets will likely be handed over to the Indonesian government, said WHO spokeswoman Maria Cheng in Geneva.

The stockpile alert came Monday as health officials puzzled over why at least six family members from the village in North Sumatra died after being infected by the H5N1 virus. A seventh was buried before tests could be done but she is believed to have been infected as well.

The virus has not yet mutated into a form easily passed among humans though scientists have seen examples of bird flu passing between family members in a handful of smaller cases.

“If this virus had evolved into a form that is more easily passed between people, you would have seen some other cases (outside the family) by now,” Cheng said. “The virus hasn’t passed beyond the family.”

The number of human bird flu cases in Indonesia has jumped rapidly this year, but public awareness of the disease remains low and government commitment has not equaled that of other countries. Indonesia’s reaction has raised concerns it is moving slowly and ineffectively in containing the disease.

Vietnam, the country hit hardest by bird flu, has been hailed for controlling the virus through mass poultry vaccination campaigns, among other measures. No human cases have been reported there since November.

Indonesia, a sprawling nation of 17,000 islands, has refused to carry out mass slaughters of poultry in all infected areas – a basic containment guideline – saying it cannot afford to compensate farmers. And bio-security measures are virtually nonexistent in the densely populated countryside, with its hundreds of millions of backyard chickens.

The WHO in Jakarta received word about the Kubu Simbelang cluster from the Indonesian Health Ministry on Monday. That led the Geneva-based organization to put Swiss drug maker Roche Holding AG on alert hours later, said Jules Pieters, director of WHO’s rapid response and containment group.

He said Roche would remain on alert for approximately the next two weeks, or twice the incubation period of the last reported case.

Roche spokesman Baschi Duerr said the stockpile, which consists of 3 million treatment courses, is ready to be shipped wherever it is needed at any time. “We are in very close contact with WHO, even today, and our readiness is geared to be able to deliver,” Duerr said.

Meanwhile, Nyoman Kandun, a director general at Indonesia’s health ministry, said Saturday that a WHO laboratory in Hong Kong had confirmed five more cases of human bird flu, three of which were fatal.

All five had earlier tested positive for the H5N1 virus in a local laboratory.

The latest confirmed deaths were a 39-year-old man from Jakarta, a 10-year-old girl from West Java and a 32-year-old man, who on Monday became the last to die in the Kubu Simbelang cluster.

Experts have been unable to link the cluster family members to contact with infected birds, and tests on poultry in the village have all come back negative. No one else in the village has fallen ill.

So far, most human cases have been traced to contact with infected poultry. But there is evidence of isolated cases of limited transmission between people in very close contact with each other.

Scientists are unsure how this has occurred, but they have theorized that the virus may pass from one person to another through droplets sneezed or coughed by humans into the air or food, onto surfaces or in some combination.

It has been suggested that some people may have a genetic susceptibility to the disease. In all four family clusters recorded so far, only direct blood relatives – not spouses – have caught bird flu.

Experts were 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.

Health officials have struggled to gather information in the village or take blood samples from residents, many of whom believe black magic is responsible for their neighbors’ deaths.


Associated Press reporter Zakki Hakim in Jakarta and Sam Cage in Geneva contributed to this report.

AP-ES-05-27-06 1758EDT