JAKARTA (Reuters) - A 15-year-old Indonesian boy has tested positive for the H5N1 bird flu, a senior health ministry official said on Wednesday, citing results of a local laboratory.

These results are not considered definitive and samples are on their way to a World Health Organisation-accredited laboratory in Hong Kong for confirmation.

"Usually, if local tests are positive it´s also positive in Hong Kong," said Hariadi Wibisono, director of animal-borne disease control at the Health Ministry.

The boy, from Tasikmalaya town in west Java, was admitted to hospital on May 29 and died a day later.

Government officials who visited the boy´s village found that he had contact with infected poultry near his home and his own chickens died two weeks ago. The boy´s grandfather was a chicken farmer and 40 of his chickens died recently.

Although the virus primarily causes disease in birds, many countries around the world are on alert for it as they fear it may mutate into one that spreads easily among people and trigger a pandemic, killing millions.

Indonesia is of particular concern because of the steady rise in its number of human infections and deaths since its first known outbreak of H5N1 in chickens in late 2003. Forty-nine people have been infected and 36 of them have died.

Fears intensified earlier this month, when the virus killed as many as seven members of a single family in north Sumatra, and experts later said there could have been limited human-to-human transmission in this cluster case.

But they stressed that genetic analyses of the virus has not shown all of the traits that are known so far to allow it to spread easily among people.

Officials combating the disease will seek to educate citizens about the disease in a campaign in Medan on Thursday, said Bayu Krisnamurthi of the National Committee on Avian Influenza Control and Pandemic Influenza Preparedness.

"It´s a combination of poverty, little education and tendency to compare flu to other diseases or misfortunes. Without enough understanding, people see this as minor," he said.

"We want to give more information, teach them about the disease, about possibly greater damage if there are no changes."