Two Indonesian teenagers have died of the bird flu virus, bringing the country's number of human fatalities to 44, Indonesian health officials say.
Bird flu is endemic in poultry in Indonesia
The test results mean Indonesia now has the world's highest human death toll from the H5N1 virus.
Tests at two local laboratories showed a 16-year-old boy died of the disease on Monday a 17-year-old girl died on Tuesday, officials said.
Indonesia has registered more bird flu deaths this year than any other nation.
Vietnam has also been badly affected, suffering 42 deaths since 2003, but the outbreak there seems to be under control.
No one has died from the disease in Vietnam since the beginning of 2006.
Indonesia has recently changed the way it confirms human bird flu deaths with the World Health Organisation.
In the past, samples were tested at a WHO-affiliated laboratory before official confirmation was given.
But now, if two national laboratories confirm the presence of the virus, it is officially classified as a bird flu death and the WHO is informed.
Officials said the 16-year-old girl was admitted to hospital on 4 August in Tangerang, west of Jakarta, but died before she could be transferred to the capital.
The teenage boy came from Bekasi on the outskirts of Jakarta.
He was admitted to the city's designated bird flu centre, Sulianti Suroso hospital, on Saturday, and his condition rapidly deteriorated.
Health officials said he had been in contact with sick chickens before he contracted the disease.
Transmission from poultry is the main cause of human bird flu, but there is a fear that the virus could mutate to a form which could be easily passed from human to human, triggering a pandemic and potentially putting millions of lives at risk.
Indonesia's problems were highlighted in May when the country recorded a large cluster of deaths which the WHO believes were the result of human-to-human transmission.
The 16-year-old boy had been in contact with sick poultry
But experts say this particular incident did not signal a major change in the spread of the disease. Indonesia has often been criticised for its reluctance to cull large numbers of fowl - a method that has proved effective in other nations.
But the disease is endemic in poultry across most of the country, and the government says it is simply not practical to initiate such a widespread cull.
It also says it does not have enough money to compensate farmers, and has asked for $900m (£495m) over the next three years to tackle the virus.
Globally, more than 130 people have died of bird flu since late 2003. Most of the deaths have been in East Asia, but the virus has also spread to Europe, Africa and South and Central Asia.