GENEVA—The World Health Organisation (WHO) on Thursday retrospectively recognised a further two cases of bird flu in Indonesia, including one where human-to-human transmission could not be ruled out between siblings.
The United Nations agency said fresh results had shown that a 27-year-old man from West Sumatra province, who cared for his 15-year-old sister in hospital last May, had also been infected with the H5N1 virus despite initially testing negative.
"The 27-year-old male reported no contact with diseased or dead poultry in the days prior to symptom onset as he spent most of his time at the hospital," the WHO said in a statement.
"The investigation determined that he had exposure to his sister during her hospital stay and that human-to-human transmission could not be ruled out as the source of his infection," it said.
The man, who had "mild and atypical symtpoms", was treated with Swiss drug maker Roche's anti-viral Tamiflu and placed in voluntary isolation, according to WHO.
Both he and his sister recovered.
The WHO also accepted that a five-year-old boy, who died last March in Jakarta, had died of bird flu after being exposed to diseased poultry near his home. Indonesian health authorities announced the case on Wednesday, citing fresh test results.
The retrospectively confirmed bird flu cases, which follow three others announced last Friday, bring the total in Indonesia to 65, including 49 fatalities, according to the WHO.
The national death toll is the world's highest from the disease which affectes mainly animals but which experts fear could mutate into a pandemic strain capable of killing millions of people.
Indonesia has been criticised for not doing enough to combat the disease, which is endemic in birds in most of the sprawling archipelago's provinces.
The largest known cluster of human bird flu cases worldwide occurred in May in the Karo district of North Sumatra province, where as many as seven people in an extended family died, the WHO said.
The latest confirmed cases bring the global total to 246 cases in 10 countries since 2003, with 144 deaths, it said.
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