A 2-1/2-year-old Indonesian boy has died of bird flu, taking the country´s human death toll from the virus to 56, a health ministry official said on Monday.

The toddler from Karawang regency in West Java province had had contact with fowl, the most common method of transmission of the virus, Ningrum, an official at the health ministry´s bird flu center, told Reuters.

Another health ministry official said a 35-year-old woman from a different part of West Java was also being treated for bird flu in a Jakarta hospital, but it was not clear if she had had any contact with fowl.

The two victims are not related, Dr. Muhammad Nadhirin, from the ministry´s national bird flu center, told Reuters.

Bird flu remains essentially an animal disease but it has infected more than 250 people worldwide since late 2003, killing more than 150, according to the World Health Organization.

Indonesia has become one of the frontlines in the battle against the disease. No country has suffered from more deaths than this huge Asian country of 17,000 islands where millions of chickens roam backyards freely.

Despite the rise in the human death toll, the Indonesian government has resisted mass culling of birds, citing the expense and impracticality in a sprawling, populous country where many people are still unperturbed by the bird flu threat.

The number of provinces where bird flu is endemic has nearly halved in the last six months, although all areas on heavily populated Java island remain affected, officials say.

Scientists fear the virus could mutate into a form that can be passed easily between people, leading to a possible human pandemic which could kill millions.