New research suggests that avian flu may transmit to from human to human.
June 23, 2012– New research found that human-to-human transmission is possible in avian H5N1 viruses in the future. The new findings, from the University of Cambridge, were led by Dr. Colin Russell and Professor Derek Smith. At this time, avian H5N1 influenza also referred to as the bird flu, can be transmitted to humans from birds, but not between humans.
However, two recent research papers revealed the possibility, with as little as five mutations, that H5N1 influenza could become airborne transmittable in mammals and thus would potentially be transmittable amongst humans. Until now however, it was unknown whether the mutations needed might evolve in nature or not.
The researchers analyzed all data available on the different strains of avian H5N1 influenza over the past 15 years, with the focus on humans and birds. The researchers discovered that already two of the five mutations in the experimental viruses had occurred in a number of flu strains now in existence. In addition, they found a number of the viruses contained both of the mutations.
Factors that increase the likelihood that mutation might occur included long infection, diversity within the bird virus population, functionality of substitutes, random infection and transmission through mammals.
Factors decreasing the likelihood that mutation would evolve are effective immune response, deleterious substitution and the order of acquiring the mutations.