PB2-E627K and PA-T97I substitutions enhance polymerase activity and confer a virulent phenotype to an H6N1 avian influenza virus in mice.
Cheng K, Yu Z, Chai H, Sun W, Xin Y, Zhang Q, Huang J, Zhang K, Li X, Yang S, Wang T, Zheng X, Wang H, Qin C, Qian J, Chen H, Hua Y, Gao Y, Xia X.
Virology. 2014 Sep 3;468-470C:207-213. doi: 10.1016/j.virol.2014.08.010.
This illustrates the difficulties in interpreting viral mutations. The work does not involve airborne transmission but the authors had previously serially adapted the avian H6N1 virus to mice. Adaptation was accompanied by three mutations two of which render the virus more pathogenic than the initial virus and are the subject of the study. To date there has only been one symptomatic case of H6N1 infection in humans so the potential of such avian viruses is totally unclear. It is yet another example of the adaptability of influenza and other RNA viruses to a new experimental environment.
