A 27-year-old Indonesian woman died in a Jakarta hospital on Monday after suffering from bird flu, and a five-year-old girl who died last week was suspected to have carried the disease, officials said on Monday.

The disease had already killed four people in the sprawling country with the world’s fourth highest population.

Sardikin Giriputro, deputy head of the hospital designated by the government to treat patients with suspected bird flu, said the woman had been admitted on Thursday.

“It’s confirmed H5N1,” I Nyoman Kandun, who heads disease control at the health ministry, told a news conference, describing the most deadly strain of bird flu.

It was unclear how the woman got the disease, but she had been in contact with chickens that died from an unknown cause. Many urban-area households in Indonesia keep livestock, especially chickens, in their yards.

“According to her family, 15 chickens in her home died, but we don’t know whether the chickens had died because of bird flu or not,” Giriputro had said.

Indonesia’s health ministry now puts the death toll from bird flu at six because a local test on a five-year-old girl showed positive.

By World Health Organization standards, however, the final proof rests on the outcome of a PCR (Polymerase Chain Reaction) test, which in the girl’s case showed negative.

Bird flu has killed 65 people in four Asian nations since late 2003 and has been found in birds in Russia and Europe.

The virus has spread to 22 provinces out of 33 in the Indonesian archipelago, killing more than 9.5 million domesticated birds since 2003. Indonesia said this week it would cull poultry in areas where the outbreak was serious.

Giriputro said five out of 22 people who had been admitted to the hospital were allowed to go home because they had been found not to have the disease.

Experts’ greatest fear now is that the H5N1 virus, which has the power to kill one out of every two people in infects, could set off a pandemic if it gains the ability to be passed easily among people.

While they say the virus could have passed in a few cases from person to person who had had very close and sustained contact in the last two years, it has yet to mutate into a form which would allow it to do that easily.

Health Minister Siti Fadillah Supari said on Monday 20,000 doses of the anti-viral drug Tamiflu were expected to arrive in Indonesia by Tuesday and a further 20,000 would come by the end of this week.

Australian Foreign Minister Alexander Downer said Canberra will pay for a further 40,000 doses of the anti-viral drug Tamiflu for Indonesia, on top of an initial 10,000 doses that Canberra said on Friday it would fund.

“I think they have been caught a bit short, to tell you the truth, and they are finding it difficult to handle,” Downer told reporters in Adelaide. “We’re doing everything we can to help them and so we should as a next-door neighbor.”