Fergie's Tech Blog

WHO: Significance of Mutations in the H5N1 Virus

Via The World Health Organization (WHO).

Several recent media reports have included speculations about the significance of mutations in H5N1 avian influenza viruses. Some reports have suggested that the likelihood of another pandemic may have increased as a result of changes in the virus.

Since 1997, when the first human infections with the H5N1 avian influenza virus were documented, the virus has undergone a number of changes.

These changes have affected patterns of virus transmission and spread among domestic and wild birds. They have not, however, had any discernible impact on the disease in humans, including its modes of transmission. Human infections remain a rare event. The virus does not spread easily from birds to humans or readily from person to person.

Influenza viruses are inherently unstable. As these viruses lack a genetic proof-reading mechanism, small errors that occur when the virus copies itself go undetected and uncorrected. Specific mutations and evolution in influenza viruses cannot be predicted, making it difficult if not impossible to know if or when a virus such as H5N1 might acquire the properties needed to spread easily and sustainably among humans. This difficulty is increased by the present lack of understanding concerning which specific mutations would lead to increased transmissibility of the virus among humans.

posted by Fergie @ 2/20/2006 10:42:00 AM