For comparison with other contemporary influenza A(H3N2) sequences worldwide between 1997-2006, all publicly available (at the time of this analysis) dated HA and NA sequences from children of similar ages (0-16 years old -the upper range was extended to include more sequences), spanning this period were downloaded from the then TIGR (The Institute for Genomics Presence/absence of established N2 neuraminidase inhibitor (NAI) resistance-associated mutations, R292K and E119V