Correlation of significant mutation sites on HA and NA genes between severe and non-severe cases of H1N1pdm infection.

aUpper respiratory tract infection. bPneumonia, Acute respiratory distress syndrome, Expired. *Fisher’s exact test.a. 上呼吸道感染（upper respiratory tract infection） b. 肺炎、急性呼吸窘迫综合征（Acute respiratory distress syndrome）、死亡（Expired） *费希尔精确检验（Fisher’s exact test）