Jan 26, 2005 (CIDRAP News) - A reported family cluster of H5N1 avian influenza cases among three brothers in Vietnam may turn out to be only two cases, the World Health Organization (WHO) said today.
Contrary to some media reports, the WHO said the 36-year-old younger brother of two men who contracted the disease has not been sick, though test results are still pending.
As reported previously, a 46-year-old man and his 42-year-old brother had confirmed H5 avian flu cases, the WHO said. The older man died Jan 9, but the 42-year-old, who cared for his older brother while the latter was sick, has recovered.
A Chinese news agency had reported Jan 24 that the 36-year-old brother also had tested positive for avian flu. But the WHO said, "The third brother, aged 36 years, was hospitalized for observation only, did not develop symptoms, and remains in good health. Results of tests, conducted as part of the investigation, are pending."
Previous reports have said the three brothers had shared a meal that included a dish containing raw duck blood, triggering speculation that they acquired avian flu that way. But the WHO did not comment on that theory today, saying only, "The source of infection for the two brothers remains undetermined and investigations are ongoing."
No evidence of additional cases has been found in the two communities where the brothers lived, the WHO said.
The agency fears that the H5N1 could launch a pandemic if it develops the ability to spread easily from person to person. The only case so far where person-to-person transmission is believed to have occurred was in Thailand last September, when an 11-year-old girl probably passed the disease to her mother and an aunt.
Today the WHO also confirmed two other H5N1 cases that were reported in the news media last weekend. They involved a 35-year-old woman from Dong Thap province, who died Jan 21, and a 17-year-old boy from Bac Lieu province, who died Jan 14.
Vietnam has had 10 confirmed human cases, 9 of them fatal, since mid-December, the WHO said. Vietnam now has had 37 confirmed cases, 29 of them fatal, since January 2004, while Thailand has had 17 cases with 12 deaths, according to the WHO.
Jan 26 WHO statement