The strain of bird flu that killed seven Indonesian family members in May was mutating as it spread from person to person, according to confidential data presented at a closed meeting of experts last month.
The news, revealed today (13 July) by Nature, has prompted fresh calls for genetic data on bird flu viruses to be made more readily available.
The family cluster was the first that the World Health Organization (WHO) said was likely to have involved human-to-human transmission.
Most of the mutations that the H5N1 virus accumulated as it spread from one person to another appear to be benign, but one confers resistance to the antiviral drug amantadine.
Researchers say it is essential to know how the virus is changing as it spreads, but the WHO has not revealed full details of the genetic changes because the data belong to Indonesia.
A senior official at the WHO points out that its remit is to investigate outbreaks, not to do academic research.
He acknowledges that greater data sharing would accelerate research on the virus, but says it is up to the countries involved to decide whether to share data.Link to full article in Nature