Indonesia has confirmed its first case of bird flu in humans. A farm worker in South Sulawesi has tested positive for the H5N1 strain of the virus, although he has shown no outward symptoms of the disease.
In the past 18 months at least 53 people across Asia are known to have died of bird flu - all of them in Cambodia, Vietnam or Thailand.
Millions of chickens and ducks have been slaughtered in an effort to control the spread of the disease.
Indonesia's agriculture ministry has reported sporadic H5N1 outbreaks in birds in various parts of the country, including Sulawesi, in the first three months of this year.
Just last month the authorities confirmed the first case of the virus in pigs.
Health officials say the farm worker's case came to light during routine testing of people who had worked with infected poultry.
Blood samples from 79 farm workers were sent to Hong Kong for examination in March.
Principally an avian disease, first seen in humans in Hong Kong, 1997
Almost all human cases thought to be contracted from birds
Isolated cases of human-to-human transmission in Hong Kong and Vietnam, but none confirmed
The worker in question was found to have produced antibodies, indicating that he had been exposed to the bird flu virus. A second test confirmed this.
It is unclear exactly when he contracted the virus, but due to the low level of antibodies found in his blood, the infection is unlikely to have been recent. QUICK
Health authorities are now testing other people who could have been exposed to the disease, such as poultry workers and veterinarians.
"We have to raise our guard once again," said Hariadi Wibisono, the head of the department responsible for animal diseases.
"There is a possibility we will find more cases, but we hope that this does not transpire," he told the Associated Press.
So far humans have only contracted bird flu after coming into contact with infected animals.
But the real fear is that the virus might develop into a form which can be transmitted from person to person, spreading rapidly and raising the possibility of a global pandemic.
