JAKARTA, Sept 6 (Reuters) - An Indonesian man has died of bird flu on Sumatra island after coming in contact with sick poultry, bringing the number of people killed by the disease to 85, local health officials said on Thursday.

Officials from the World Health Organisation could not immediately be reached for comment.

The 33-year-old victim, who came from Riau province, fell sick soon after slaughtering and cooking a sick chicken he bought in a nearby market, said Muhammad Nadirin, an official at the health ministry"e;s bird flu centre.

Genetic sequencing tests by an Indonesian laboratory showed that the man had contracted the deadly H5N1 virus, health ministry official Endang Sedyaningsih told Reuters.

Previously, tests from two separate facilities were required by the World Health Organisation (WHO) to confirm a bird flu case, but only one lab carried out the test this time.

The official said that an expert from a second laboratory, Eijkman, which usually conducts a second test, was present for the test. He didn"e;t elaborate.

Excluding this case, Indonesia has had 105 confirmed cases, out of which 84 had been fatal, the highest for any country in the world.

Also excluding the latest case, there have been 327 cases and 199 deaths globally since 2003, World Health Organisation data shows.

The man went to a number of hospitals after suffering fever and breathing difficulties on Aug. 27, before being admitted to a state hospital in the provincial capital Pekanbaru on Sunday, Saad said.

Azizman Saad, head of bird flu management at the Arifin Achmad Hospital in Pekanbaru, said the man had also buried a chicken that was found dead in his backyard.

Sick fowl is the most common way for humans to contract the virus.

Bird flu is endemic in bird populations in most parts of Indonesia, where millions of backyard chickens live in close proximity to people.

While it is largely an animal disease, experts fear the virus could mutate and spread from human to human, turning into pandemic that could kill millions. ((Reporting by Mita Valina Liem; Writing by Adhityani Arga; editing by Sanjeev Miglani;ed.davies@reuters.com; Reuters Messaging; ed.davies.reuters.com@reuters.net; tel +6221 384 6364))