bird flu mutation

Last Update: Monday, March 14, 2005. 8:08pm (AEDT)
WHO warns of human bird flu mutation
The World Health Organisation (WHO) says the bird flu virus may be changing into a form that humans can pass on.

The WHO is worried that bird flu, which has killed 47 people in Asia, could mutate into an easily spread form that sparks the next influenza pandemic.

The organisation has identified a cluster of human bird flu cases among relatives and possibly health workers in Vietnam.

"Such cases can provide the first signal that the virus is altering its behaviour in human populations and thus alert authorities to the need to intervene quickly," the WHO said in a statement.

The main concern of the WHO was a series of cases of the deadly H5N1 bird flu virus in a family in the northern Vietnam province of Thai Binh and the possible infection of two nurses who cared for one of the patients.

The WHO also says it has received confirmation of an additional 10 cases of human infections from Vietnam's Health Ministry.

The new cases were detected in early March or through re-examination of older cases, some of which dated back to late January and three of which had been fatal, the WHO said.