JAKARTA (Reuters) - Indonesia's Health Ministry said on Tuesday testing had confirmed that a man who died in September was positive for bird flu, raising the number of deaths from the virus in the country to four. 

Hariadi Wibisono, a senior official at the ministry, also said the number of other Indonesians who had fallen sick from the virus but were still alive had risen to three from two. 

"The confirmed cases are seven, of whom four have died.

Three are still alive," Wibisono said. 

He said the latest results were from tests obtained on Monday and verified by the World Health Organization (WHO). 

The latest confirmed death was of a 23-year-old man from Bogor, a town near Jakarta. 

The latest surviving case was a four-year-old boy from Lampung province in southern Sumatra whom local media have said is the nephew of a 21-year-old man who has also tested positive and is still alive. 

The precise condition of the three surviving Indonesian cases was not immediately known. 

Concern about the deadly H5N1 strain of bird flu centres on scientists' fears that it may mutate into a form that passes easily among humans, sparking a pandemic that may kill millions. 

The WHO has said possible cases of bird flu among family members in Indonesia did not mean the deadly virus was mutating, but could be caused by close contact normal in families. 

More than 60 people have died from bird flu in Southeast Asia, the most likely epicentre of any human pandemic, but the virus has also been moving steadily from Asia into birds in Europe since re-emerging in South Korea in 2003. 

Some health experts worry Indonesia is not showing enough urgency in tackling bird flu, especially in culling chickens. The government has defended its response, saying for example that it does not have enough money to compensate farmers.