Sociodemographic, clinical and epidemiological characteristics according to Influenza A (H1N1)pdm09 HA 222 polymorphisms.

WT, wild type D222; Pandemic period (EW 17/2009 to 9/2010); Post pandemic period (EW 22/2011 to 35/2011); Serious cases were defined as those who presented SARI or pneumonia and/or demanded hospitalization; EW, epidemiological week. 1G222 or mixed populations - regarded as the polymorphisms G/N; G/D; N/D or N/G/D at the 222 HA residue. *Associations were assessed by Pearson Chi-square tests and p value was considered significant when