Killer H5N1 bird flu strain 'mutated slightly'

A World Health Organisation (WHO) investigation showed that the H5N1 virus mutated slightly in an Indonesian family cluster on Sumatra island.

The virus that infected eight members of a family last month – killing seven of them – appears to have slightly mutated in a 10-year-old boy, who is then suspected of passing the virus to his father, the WHO investigative report said.

But bird flu experts insist the case did not increase the possibility of a human pandemic.

It is the first evidence indicating that a person caught the virus from a human and then passed it on to another person, said Tim Uyeki, an epidemiologist from the US Centres for Disease Control and Prevention.

He said the H5N1 virus died with the father and did not pass outside the family.

“It stopped. It was dead end at that point,” he said, stressing that viruses are always slightly changing and there was no reason to raise alarm.

Dr William Schaffner, a bird flu expert at the Vanderbilt University, called the mutation “noteworthy but not worrisome.” Generally it takes a series of mutations in a bird flu virus to raise the danger of a pandemic in humans, he said.

Dr Schaffner said it is remarkable that scientists were able to discover a mutation that occurred in a remote village in Indonesia.

The findings appeared in a report that was distributed at a closed meeting in Jakarta attended by some of the world’s top bird flu experts.

The three-day session was convened after Indonesia asked for international help. The country has experienced an explosion of human bird flu cases this year and is on pace to become the world’s hardest-hit nation with 39 deaths.